Process for the preparation of a block copolymer comprising a first polyolefin block and a second polymer block as well as the products obtained therefrom

ABSTRACT

The present invention relates to a cascade process for the preparation of a block copolymer comprising a first type of polyolefin block and at least one type of second polymer block. The process according to the present invention involves the following consecutive steps: A) polymerizing at least one type of olefin monomer using a catalyst system to obtain a first polyolefin block containing a main group metal on at least one chain end; the catalyst system comprising: i) a metal catalyst or metal catalyst precursor comprising a metal from Group 3-10 of the IUPAC Periodic Table of elements; and ii) at least one type of chain transfer agent; and iii) optionally a co-catalyst; B) reacting the first polyolefin block containing a main group metal on at least one chain end obtained in step A) with at least one type of oxidizing agent to obtain a first polyolefin block containing at least one main group metal-functionalized oxidized chain end; and C) forming at least one second polymer block on the first polyolefin block, wherein as a catalytic initiator the main group metal-functionalized oxidized chain end of the first polyolefin block obtained in step B) is used.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 371 of International Application No. PCT/EP2015/080336, filed Dec. 17, 2015, which claims priority to European Application No. 14198482.3, filed Dec. 17, 2014 which are incorporated herein by reference in their entirety.

The present invention relates to a process for the preparation of a block copolymer comprising a first polyolefin block and at least one second polymer block using a cascade-like process and the products obtained therefrom.

BACKGROUND

The present invention relates to the preparation of block copolymers comprising a first polyolefin block and at least one second polar or nonpolar polymer block and the products obtained therefrom.

Block copolymers combining a polyolefin block with a polyethylene-like polymer block are useful as compatibilizers for blends of e.g. polyethylene (PE) and other polyolefins (e.g. iPP). The preparation of actual polyolefin-PE block copolymers (e.g. iPP-b-PE) is a very tedious process that requires a living catalyst or a chain transfer polymerization process including intermediate venting steps to produce block copolymers consisting of well-defined iPP and PE blocks.

Block copolymers combining a polyolefin block with at least one polar polymer block may be used to enhance the properties of polyolefin polymers that have an inherent nonpolar character that leads to drawbacks for certain applications, because of poor adhesion, printability and compatibility that can restrict their efficacy. Furthermore, block copolymers combining a polyolefin block with a polar polymer block are useful as compatibilizers for blends of e.g. polyolefins (e.g. iPP) and polar polymers (e.g. polyester or polycarbonate).

In the prior art different approaches have been reported for the preparation of polyolefin-based block copolymers, based on either living catalysts or chain transfer concepts for polymerizations mediated by homogeneous single-site catalysts, being a metal catalyst that consists of solely one type of catalytically active site. The prior art describes the preparation of chain-end functionalized polyolefins in a separate process, which are subsequently used as initiators for forming the corresponding block copolymers using an additional catalyst.

WO 2011/014533 of Dow Global Technologies discloses the use of a multifunctional chain transfer agent that can be used in preparing polyethylene-b-caprolactone block copolymers.

Other prior art documents (e.g. Han, Macromolecules, 2002, 35, 8923-8925; and Chung et al. Polymer 2005, 46, 10585-10591) use a process, which goes via a polyolefin-OH intermediate compound. This includes intermediate isolation, purification and drying of said functional polyolefin. Subsequent ring-opening polymerization reaction (ROP) is carried out using a catalyst system.

Other, related prior art (Becquart, Macromol. Mater. Eng. 2009, 294, 643-650) uses a process where poly(ethylene-co-vinyl alcohol) (EVOH) is applied as a poly(hydroxyl) functionalized polyethylene and treated with a polyester in the presence of SnOct₂ as transesterification catalyst to form the corresponding EVOH-graft-polyester graft copolymers.

For example, polyolefin-polar or polyolefin-nonpolar block copolymers can be obtained by first preparing two separate blocks and subsequently coupling these blocks. Another way of preparing them consists of using a polyolefin having a functional end group as initiator to grow a polar or nonpolar polymer from it.

It is an aim of the present invention to provide a catalyst system allowing efficient chain transfer in the preparation of metal functionalized polyolefins, which after oxidation of the metal-functionalized polyolefins which can be applied as catalytic initiators for the formation of polyolefin-based block copolymers.

It is moreover an aim of the present invention to produce A-B or A-B-C- . . . type di-, tri or multiblock copolymers having one polyolefin block (A) and at least one polar or polyethylene-like polymer block (B and/or C).

It is moreover an aim of the present invention to produce B-A-B or . . . -C-B-A-B-C- . . . tri-, penta- or multiblock copolymers having a central polyolefin block (A) flanked on each side by at least one other polymer block, either polar or nonpolar (B and/or C).

It is moreover an aim of the present invention to provide polymers that can be used as compatibilizers for blends of polyolefins (e.g. iPP) with polar polymers such as polycarbonate or nonpolar polymers such as PE.

One or more of these aims are obtained by the process according to the present invention.

SUMMARY OF THE INVENTION

The present invention relates to the novel and inventive cascade-like process for the preparation of block copolymers having a first polyolefin block and at least one second polymer block and the block copolymers obtained therefrom.

In a first aspect, the present invention relates to a process for the preparation of a block copolymer comprising a first type of polyolefin block and at least one type of second polymer block, the process comprising the steps of:

-   -   A) polymerizing at least one type of olefin monomer using a         catalyst system to obtain a first polyolefin block containing a         main group metal on at least one chain end; the catalyst system         comprising:         -   i) a metal catalyst or metal catalyst precursor comprising a             metal from Group 3-10 of the IUPAC Periodic Table of             elements; and         -   ii) at least one type of chain transfer agent; and         -   iii) optionally a co-catalyst;     -   B) reacting the first polyolefin block containing a main group         metal on at least one chain end obtained in step A) with at         least one type of oxidizing agent to obtain a first polyolefin         block containing at least one main group metal-functionalized         oxidized chain end; and     -   C) forming at least one second polymer block on the first         polyolefin block, wherein as a catalytic initiator the main         group metal-functionalized oxidized chain end of the first         polyolefin block obtained in step B) is used.

Step C) may be carried out for example by ring-opening polymerization (ROP) and/or nucleophilic substitution.

In yet another embodiment, step C) of obtaining a block copolymer is carried out by a ring-opening polymerization (ROP) using at least one type of cyclic monomer.

In an embodiment, step C) of obtaining a block copolymer is carried out by a nucleophilic substitution reaction at a carbonyl group-containing functionality of at least one second polymer.

In another embodiment, step C) of obtaining a block copolymer is carried out by transesterification of at least one second polymer comprising at least one carboxylic or carbonic acid ester functionality.

In an embodiment, step C) comprises two sub-steps so that e.g. a triblock or pentablock copolymer is formed (A-B-C or C-B-A-B-C, wherein A is a polyolefin and B and C are both polymer blocks with different monomers).

In yet another embodiment, step B) is carried out directly after step A) and/or wherein step C) is carried out directly after step B), preferably in a series of connected reactors, preferably continuously.

In yet another embodiment, during step C) no additional catalyst for the ROP is added. In yet another embodiment, during step C) no additional catalyst for the transesterification reaction is added. In yet another embodiment, during step C) no additional catalyst for the nucleophilic substitution reaction is added.

In yet another embodiment, the metal catalyst or metal catalyst precursor used in step A) comprises a metal from Group 3-8 of the IUPAC Periodic Table of elements.

In yet another embodiment, the metal catalyst or metal catalyst precursor used in step A) comprises a metal from Group 3-6 of the IUPAC Periodic Table of elements.

In yet another embodiment, the metal catalyst or metal catalyst precursor used in step A) comprises a metal from Group 3-4 of the IUPAC Periodic Table of elements.

In yet another embodiment, the metal catalyst or metal catalyst precursor used in step A) comprises a metal selected from the group consisting of Ti, Zr, Hf, V, Cr, Fe, Co, Ni, Pd, preferably Ti, Zr or Hf.

In yet another embodiment, the co-catalyst is selected from the group consisting of MAO, DMAO, MMAO, SMAO and fluorinated aryl borane or fluorinated aryl borate.

In yet another embodiment, the at least one olefin monomer used in step A) is selected from the group consisting of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-cyclopentene, cyclohexene, norbornene, ethylidene-norbornene, and vinylidene-norbornene and one or more combinations thereof.

In yet another embodiment, the cyclic monomer used during ROP in step C) to obtain the block copolymer is a is a polar monomer, selected from the group consisting of lactone, a lactide, a cyclic oligoester (e.g. a di-ester, a tri-ester, a tetra-ester, a penta-ester or higher oligoesters), an epoxide, an aziridine, a combination of epoxide and/or aziridine and CO₂, a cyclic anhydride, a combination of epoxide and/or aziridine and a cyclic anhydride, a combination of epoxide and/or aziridine and CO₂ and a cyclic anhydride, a cyclic N-carboxyanhydride, a cyclic carbonate, a lactam, and one or more combinations thereof.

In yet another embodiment, the cyclic monomer used during ROP in step C) to obtain the block copolymer is a cyclic monomer comprising a carbonyl group-containing functionality and at least 10 consecutive carbon atoms in the ring/cycle, preferably selected from the group consisting of cyclic esters, cyclic carbonates, cyclic amides, cyclic urethanes and cyclic ureas; or one or more combinations thereof, preferably selected from the group consisting of cyclic esters, cyclic carbonates, cyclic amides, cyclic urethanes and cyclic ureas; or one or more combinations thereof.

In yet another embodiment, the second polymer added in step C block comprises at least one carboxylic or carbonic acid ester functionality or a carbonyl-group containing functionality is selected from the group consisting of a polyester, a polycarbonate, a polyamide, a polyurethane, a polyurea, a random or block poly(carbonate-ester), poly(carbonate-ether), poly(ester-ether), poly(carbonate-ether-ester), poly(ester-amide), poly(ester-ether-amide), poly(carbonate-amide), poly(carbonate-ether-amide), poly(ester-urethane), poly(ester-ether-urethane), poly(carbonate-urethane), poly(carbonate-ether-urethane), poly(ester-urea), poly(ester-ether-urea), poly(carbonate-urea), poly(carbonate-ether-urea), poly(ether-amide), poly(amide-urethane), poly(amide-urea), poly(urethane-urea), or one or more combination thereof.

In yet another embodiment, the chain transfer agent is a main group metal hydrocarbyl or a main group metal hydride.

In yet another embodiment, the chain transfer agent is selected from the group consisting of hydrocarbyl aluminum, hydrocarbyl magnesium, hydrocarbyl zinc, hydrocarbyl gallium, hydrocarbyl boron, hydrocarbyl calcium, aluminum hydride, magnesium hydride, zinc hydride, gallium hydride, boron hydride, calcium hydride and one or more combinations thereof.

In a preferred embodiment, the main group metal chain transfer agent is selected from the group consisting of: hydrocarbyl aluminum, hydrocarbyl magnesium and hydrocarbyl zinc and one or more combinations thereof, more preferably hydrocarbyl aluminum.

In yet another embodiment, the chain transfer agent is selected from the group consisting of trialkyl boron, dialkyl boron halide, dialkyl boron hydride, diaryl boron hydride, dialkyl boron alkoxide, dialkyl boron aryloxide, dialkyl boron amide, dialkyl boron thiolate, dialkyl boron carboxylate, dialkyl boron phosphide, dialkyl boron mercaptanate, dialkyl boron siloxide, dialkyl boron stannate, alkyl boron dialkoxide, alkyl boron diaryloxide, alkyl boron dicarboxylate, alkyl boron diphosphide, alkyl boron dimercaptanate, alkyl boron disiloxide, alkyl boron distannate, boron hydride dialkoxide, boron hydride diaryloxide, boron hydride diamide, boron hydride dicarboxylate, boron hydride diphosphide, boron hydride dimercaptanate, boron hydride disiloxide, boron hydride distannate, trialkyl aluminum, dialkyl aluminum halide, dialkyl aluminum hydride, dialkyl aluminum alkoxide, dialkyl aluminum aryloxide, dialkyl aluminum amide, dialkyl aluminum thiolate, dialkyl aluminum carboxylate, dialkyl aluminum phosphide, dialkyl aluminum mercaptanate, dialkyl aluminum siloxide, dialkyl aluminum stannate, alkyl aluminum dialkoxide, alkyl aluminum diaryloxide, alkyl aluminum dicarboxylate, alkyl aluminum diphosphide, alkyl aluminum dimercaptanate, alkyl aluminum disiloxide, alkyl aluminum distannate, aluminum hydride dialkoxide, aluminum hydride diaryloxide, aluminum hydride diamide, aluminum hydride dicarboxylate, aluminum hydride diphosphide, aluminum hydride dimercaptanate, aluminum hydride disiloxide, aluminum hydride distannate, trialkyl gallium, dialkyl gallium halide, dialkyl gallium hydride, dialkyl gallium alkoxide, dialkyl gallium aryloxide, dialkyl gallium amide, dialkyl gallium thiolate, dialkyl gallium carboxylate, dialkyl gallium phosphide, dialkyl gallium mercaptanate, dialkyl gallium siloxide, dialkyl gallium stannate, dialkyl magnesium, diaryl magnesium, alkyl magnesium halide, alkyl magnesium hydride, alkyl magnesium alkoxide, alkyl magnesium aryloxide, alkyl magnesium amide, alkyl magnesium thiolate, alkyl magnesium carboxylate, alkyl magnesium phosphide, alkyl magnesium mercaptanate, alkyl magnesium siloxide, alkyl magnesium stannate, dialkyl calcium, alkyl calcium halide, alkyl calcium hydride, alkyl calcium alkoxide, alkyl calcium aryloxide, alkyl calcium amide, alkyl calcium thiolate, alkyl calcium carboxylate, alkyl calcium phosphide, alkyl calcium mercaptanate, alkyl calcium siloxide, alkyl calcium stannate, dialkyl zinc, alkyl zinc halide, alkyl zinc hydride, alkyl zinc alkoxide, alkyl zinc aryloxide, alkyl zinc amide, alkyl zinc thiolate, alkyl zinc carboxylate, alkyl zinc phosphide, alkyl zinc mercaptanate, alkyl zinc siloxide, alkyl zinc stannate, and or more combinations thereof, preferably trimethyl aluminum (TMA), triethyl aluminum (TEA), tri-(i-butyl) aluminum (TIBA), di(isobutyl) aluminum hydride (DIBALH), di(n-butyl) magnesium (DBM), n-butyl(ethyl)magnesium, benzyl calcium 2,6-di(t-butyl)-4-methyl-phenoxide, dimethyl zinc, diethyl zinc (DEZ), trimethyl gallium, or triethylboron, 9-borabicyclo(3.3.1)nonane, catecholborane, and diborane and one or more combination thereof.

Preferably, the CTA is selected from the group consisting of TIBA, DIBALH, DBM and DEZ. In yet another embodiment, the at least one oxidizing agent in step B) is selected from the group consisting of O₂, CO, O₃, CO₂, CS₂, COS, R²NCO, R²NCS, R²NCNR³, CH₂═C(R²)C(═O)OR³, CH₂═C(R²)(C═O)N(R³)R⁴, CH₂═C(R²)P(═O)(OR³)OR⁴, N₂O, R²CN, R²NC, epoxide, aziridine, cyclic anhydride, R³R⁴C═NR², SO₃, and R²C(═O)R³, or a combination of NH₃ and NaClO or a combination of H₂O₂ and NaOH, where R², R³, R⁴, R⁵ and R⁶ are each independently selected from hydrogen or SiR⁷ ₃, SnR⁷ ₃ or a C1-C16 hydrocarbyl, preferably selected from hydrogen or C1-C6 hydrocarbyl; where each R⁷ is independently selected from hydride, halide or C1-C16 hydrocarbyl.

In yet another embodiment, the at least one oxidizing agent in step B) is selected from the group consisting of O₂, O₃, N₂O, epoxide, aziridine, CH₂═C(R²)C(═O)OR³, CH₂═C(R²)(C═O)N(R³)R⁴, CH₂═C(R²)P(═O)(OR³)OR⁴, R²C(═O)R³, R³R⁴C═NR², a combination of NH₃ and NaClO or a combination of H₂O₂ and NaOH.

In an embodiment, the present invention is related to a process for preparing a polyolefin-nonpolar polymer block—polar polymer block (A-B-C) tri block copolymer.

In an embodiment, the process does not include the presence of a polymer-OH intermediate.

In another aspect of the present invention, the invention relates to a block copolymer obtained by or obtainable by a process according to the present invention.

Definitions

The following definitions are used in the present description and claims to define the stated subject matter. Other terms not cited below are meant to have the generally accepted meaning in the field.

“functionalized polyolefins” as used in the present description means: a polyolefin having a functional group on one or both of the ends of the polymer.

“olefin monomer” as used in the present description means: an a hydrocarbon compound having a carbon-carbon double bond hat serves as a building block for a polyolefin.

“α-olefin” as used in the present description means: an olefin having a double bond at the α position.

“polyolefin” as used in the present description means: a polymer obtained by the polymerization of olefin monomer.

“polymer chain” as used in the present description means: a chain having a number average molecular weight (M_(n)) of at least 500 g/mol.

“copolymer” as used in the present description means: a polymer derived from more than one type of monomer.

“copolymerization” as used in the present description means: a process to produce a copolymer wherein at least two different types of monomers are used.

“block” as used in the present description means: a portion of a polymer comprising constitutional units that has at least one feature which is not present in the adjacent block(s). A block should have a sequence of monomers corresponding to a number average molecular weight (M_(n)) of at least 500 g/mol.

“block copolymer” as used in the present description means: a polymer comprising at least two blocks. For example, a block copolymer is an AB diblock or BAB triblock copolymer consisting of two different blocks, a first block (A) and a second block (B).

“first polyolefin block” as used in the present description means: a polyolefin that is functionalized on one or more chain ends. The term “first” is to specify that it is the first block to be formed of the copolymer. Depending on the reaction conditions the length of the block may vary. The “first polyolefin block” can refer to the metal functionalized polyolefin (block) or the metal-functionalized oxidized polyolefin (block) obtained in step A).

“polar polymer block” as used in the present description means: a polymer block that contains heteroatom-containing functionalities.

“main group metal-functionalized first polyolefin block” as used in the present description means: a polyolefin or first polyolefin block covalently attached to a main group metal at one or both chain ends that may be obtained by chain transfer polymerization. Said polyolefin or first polyolefin block is a hydrocarbyl chain. This can be depicted by M-Pol. In other words, “main group metal-functionalized first polyolefin block” can be considered synonymous to “main group metal-terminated polyolefin”, this can e.g. be B-terminated polyolefin, Al-terminated polyolefin, Ga-terminated polyolefin, Mg-terminated polyolefin, Ca-terminated polyolefin or Zn-terminated polyolefin.

“hydrocarbyl chain” as used in the present description means: the hydrocarbyl product of a polymerization reaction according to step A) of the present invention. It may be an oligomeric polyolefin chain having e.g. between 2 and 20 olefin units or it may be a polyolefin chain, i.e. consisting of more than 20 olefin units. It should be noted that “hydrocarbyl chain” and “hydrocarbyl” are not used as synonyms.

“hydrocarbyl” as used in the present description means: a substituent containing hydrogen and carbon atoms; it is a linear, branched or cyclic saturated or unsaturated aliphatic substituent, such as alkyl, alkenyl, alkadienyl and alkynyl; alicyclic substituent, such as cycloalkyl, cycloalkadienyl cycloalkenyl; aromatic substituent, such as monocyclic or polycyclic aromatic substituent, as well as combinations thereof, such as alkyl-substituted aryls and aryl-substituted alkyls. It may be substituted with one or more non-hydrocarbyl, heteroatom-containing substituents. Hence, when in the present description “hydrocarbyl” is used it can also be “substituted hydrocarbyl”, unless stated otherwise. Included in the term “hydrocarbyl” are also perfluorinated hydrocarbyls wherein all hydrogen atoms are replaced by fluorine atoms. A hydrocarbyl may be present as a group on a compound (hydrocarbyl group) or it may be present as a ligand on a metal (hydrocarbyl ligand).

“main group metal-functionalized oxidized first polyolefin block” or “metal-functionalized oxidized first polyolefin block” as used in the present description means: a main group metal-functionalized oxidized first polyolefin or polyolefin block, M-Ox-Pol, wherein M is a main group metal, wherein Ox is a heteroatom, selected from O, S or N, or a heteroatom-containing fragment, for example but not limited to:

-   -   —O—     -   —C(═O)—     -   —C(═NR²)—     -   —C(═O)O—     -   —C(═S)S—     -   —C(═O)S—     -   —C(═S)O—     -   —C(═O)NR²—     -   —C(═NR²)O—     -   —C(═S)NR²—     -   —C(═NR²)S—     -   —CH₂—C(R²)═C(OR³)O—     -   —CH₂—C(R²)═C(NR³R⁴)O—     -   —CH₂—C(R²)═P(OR³)(OR⁴)O—     -   —C(═NR³)NR²—     -   —C(═NR²)NR³—     -   —C(R²)═N—     -   —C(R²)(R³)C(R⁴)(R⁵)O—     -   —C(R²)(R³)C(R⁴)(R⁵)NR⁶—     -   —C(═O)—R²—C(═O)O—     -   —C(R³R⁴)—N(R²)—     -   —S(═O)₂O—     -   —C(R²)(R³)O—         where R², R³, R⁴, R⁵ and R⁶ are each independently selected from         hydrogen, or SiR⁷ ₃, SnR⁷ ₃ or a C1-C16 hydrocarbyl, preferably         selected from hydrogen or C1-C16 hydrocarbyl; where each R⁷ is         independently selected from hydride, halide or C1-C16         hydrocarbyl.

“main group metal-functionalized oxidized chain end” as used in the present description means: a main group metal-functionalized oxidized chain end of the first polyolefin block.

“second polymer block” as used in the present description means: a polymer that is prepared by polymerization from one or more chain ends of an oxidized first polyolefin block or by nucleophilic substitution onto one or more chain ends of an oxidized first polyolefin block. The term “second” is to specify that it is the second block to be formed of the copolymer. The second polymer block can thereby also be a random or block copolymer comprising at least two different monomers.

“polyethylene-like block” or “polyethylene-like polymer” or “polyethylene-like polymer block” as used in the present description refers a polymer or polymer block that is at least partially miscible with polyethylene that includes but is not limited to for example polyethylene-like polyester blocks. Such kind of polymers or polymer blocks may contain at least 60 mol % of monomer units with at least 10 consecutive between carbonyl group-containing functionalities. So, in the context of the present invention, polyethylene-like polymers considered to be nonpolar.

“cyclic monomer” as used in the present description means: a compound having a ring system which can be used as a building block in polymerization. The ring system is opened and the ring-opened monomer is attached to the growing polymer chain.

“ring-opening polymerization” or “ROP” as used in the present description means: a form of chain-growth polymerization where cyclic monomers are ring-opened and enchained to form a polymer block. It also includes the copolymerization of cyclic monomers with carbon dioxide (e.g. epoxide+CO₂).

“initiator” as used in the present description means: a reagent that is capable of initiating ROP, nucleophilic substitution or transesterification reactions when combined with a metal catalyst.

“catalytic initiator” as used in the present description means: a metal-comprising reagent that is capable of initiating and catalyzing ROP or nucleophilic substitution reactions. In other words, a catalytic initiator is a combination of a metal catalyst and an initiator.

“Lewis base ligand” as used in the present description means: a group that is capable of coordinating to the transition metal of a metal catalyst or metal catalyst precursor.

“Pol” as used in the present description means: polyolefin.

“PE” as used in the present description means: polyethylene.

“LDPE” as used in the present description means: low density polyethylene and “LLDPE” as used in the present description means: linear low density polyethylene.

LDPE and LLDPE thereby encompass polyethylene with a density for example between 0.85 and 0.95 kg/m³, that can thus also includes especially for example VLDPE and MDPE.

“HDPE” as used in the present description means: high density polyethylene.

“CL” as used in the present description means: ε-caprolactone.

“PCL” as used in the present description means: polycaprolactone.

“PLA” as used in the present description means: polylactide (L, D or DL lactide can be used).

“aPP” as used in the present description means: atactic polypropylene.

“iPP” as used in the present description means: isotactic polypropylene.

“sPP” as used in the present description means: syndiotactic polypropylene.

“EB” as used in the present description means: cyclic ethylene brassylate.

“PEB” as used in the present description means: polyethylene brassylate.

“Amb” as used in the present description means: ambrettolide.

“PAmb” as used in the present description means: polyambrettolide.

“BA” as used in the present description means: cyclic butylene adipate.

“PBA” as used in the present description means: polybutyladipate.

“BS” as used in the present description means: cyclic butylene succinate.

“PBS” as used in the present description means: polybutylsuccinate.

“aPS” as used in the present description means: atactic polystyrene.

“iPS” as used in the present description means: isotactic polystyrene.

“sPS” as used in the present description means: syndiotactic polystyrene.

“PDL” as used in the present description means: pentadecalactone.

“PPDL” as used in the present description means: polypentadecalactone.

“4M1P” as used in the present description means: 4-methyl-1-pentene.

“P4M1P” as used in the present description means: poly-4-methyl-1-pentene.

“iP4M1P” as used in the present description means: isotactic poly-4-methyl-1-pentene.

“-b-” as used in the present description means: block copolymer, e.g. HDPE-b-PCL is a block copolymer of HDPE and PCL.

“-co-” as used in the present description means: random copolymer, e.g. poly(CL-co-PDL) is a random copolymer of caprolactone (CL) and pentadecalactone (PDL).

“nucleophilic substitution” as used in the present description means: a reaction in which a nucleophile attached to a carbonyl group-containing functionality is replaced by another nucleophile.

“transesterification” as used in the present description means: a process of exchanging a nucleophilic alkoxide group of a carboxylic or carbonic acid ester. Transesterification is a special type of nucleophilic substitution using an ester or carbonate functional group.

“carboxylic acid ester functionality” as used in the present description means: an ester group (—O—C(═O)—) bonded to an organic hydrocarbyl group.

“carbonic acid ester functionality” as used in the present description means: a carbonate group (—O—C(═O)—O—) bonded to an organic hydrocarbyl group R′.

“carbonyl group-containing functionality” as used in the present description means: a carbonyl (>C═O) group bonded to organic heteroatom-containing group XR′, wherein X is selected from O, S, and NR″ wherein R′ and R″ are hydrogen or hydrocarbyl and wherein the carbonyl group is attached to the heteroatom. In the context of the present invention preferably, the second polymer block comprises as the carbonyl group-containing functionality at least one carboxylic acid ester, carbonic acid ester, amide, urethane or urea functionality. The term carbonyl group-containing functionality also includes carboxylic and carbonic ester functionalities in addition to other functionalities. A carbonyl group-containing functionality does therefore preferably refer to a reactive carbonyl group-containing functionality. In the sense of the present invention, it can accordingly preferably not refer to a ketone.

“cyclic ester” as used in the present description means: an ester compound in cyclic form.

“cyclic oligoester” as used in the present description means: a cyclic di-ester, a cyclic tri-ester, a cyclic tetra-ester or a cyclic penta-ester or higher oligomers. These are special forms of a cyclic ester and are encompassed by the definition of cyclic ester.

“lactone” as used in the present description means: a cyclic ester of a hydroxycarboxylic acid. This is encompassed by the definition of cyclic ester.

“oligolactone” as used in the present description means: a di-lactone, a tri-lactone, a tetra-lactone, a penta-lactone or a higher oligomeric lactone. These are special forms of a lactone and are encompassed by the definition of lactone.

“macrolactone” as used in the present description means: a macrocyclic lactone, being a lactone comprising an ester-functionality and at least 10 consecutive carbon atoms in the ring/cycle. These are special forms of a lactone and are encompassed by the definition of lactone.

“macrooligolactones” as used in the present description means: a mixture of cyclic macromono-, macrodi, macriotri-, macrotetra- and macropenta-lactones or higher oligomers. These are special forms of a macrolactone and are encompassed by the definition of macrolactone.

“cyclic amide” as used in the present description means: an amide compound in cyclic form. It also encompasses cyclic oligoamides being a cyclic di-amide, a cyclic tri-amide, a cyclic tetra-amide, a cyclic penta-amide or higher cyclic oligomeric amides.

“cyclic carbonate” as used in the present description means: a carbonate compound in cyclic form. It also encompasses cyclic oligocarbonates being a cyclic di-carbonate, a cyclic tri-carbonate, a cyclic tetra-carbonate, a cyclic penta-carbonate or higher cyclic oligomeric carbonates.

“cyclic urethane” as used in the present description means: a urethane compound in cyclic form. It also encompasses cyclic oligourethanes being a cyclic di-urethane, a cyclic tri-urethane, a cyclic tetra-urethane, a cyclic penta-urethane or a higher cyclic oligomeric urethane.

“cyclic ureas” as used in the present description means: a urea compound in cyclic form. It also encompasses cyclic oligoureas being a cyclic di-urea, a cyclic tri-urea, a cyclic tetra-urea, a cyclic penta-urea or higher cyclic oligomeric ureas.

“degree of chain-end-functionalization” as used in the present description means: the percentage of the original main group metal-functionalized first polyolefin block that has been oxidized to form the main group metal-functionalized oxidized first polyolefin block.

“HT SEC” as used in the present description means: high temperature size exclusion chromatography. Size exclusion chromatography can be used as a measure of both the size and the polydispersity of a polymer.

“polydispersity index (Ð)” as used in the present description means: a value that indicates the distribution of the sizes of polymer molecules (M_(w)/M_(n)). The method of measuring the Ð is explained below. M_(n) is the number average molecular weight and M_(w) is the weight average molecular weight.

“chain transfer polymerization” as used in the present description means: a polymerization reaction by which the growing polymer chain is transferred to another molecule, being the chain transfer agent. During this process a hydrocarbyl group is transferred back to the active catalyst. This process can either be reversible or irreversible. When reversible, the chain transfer agents create a controlled, living-like system.

“chain transfer agent” as used in the present description means: at lease one compound that is capable of reversibly or irreversibly interchanging hydrocarbyls and/or hydrocarbyl chains with the active catalyst. It is a metal compound comprising at least one ligand with a weak chemical bond.

“hydrocarbyl chain transfer agent” as used in the present description means: a chain transfer agent having at least one hydrocarbyl as ligand.

“additional chain transfer agent” as used in the present description means: a chain transfer agent that is present in addition to another chain transfer agent.

“chain shuttling agent” as used in the present description means: at least one compound that is capable of reversibly interchanging hydrocarbyls and/or hydrocarbyl chains between the catalysts and a chain transfer agent. It is a metal compound comprising at least one ligand with a weak chemical bond.

“catalyst system” as used in the present description means: a combination of at least two components selected from the group consisting of: a metal catalyst or a metal catalyst precursor, a co-catalyst, one or more types of chain transfer agents, etc. A catalyst system always includes a metal catalyst or a metal catalyst precursor.

“catalyst” as used in the present description means: a species providing the catalytic reaction.

“metal catalyst” as used in the present description means: a catalyst comprising at least one metal center that forms the active site. In the context of the present invention a “metal catalyst” is the same as a “transition metal catalyst” wherein the metal is a transition metal.

“metal catalyst precursor” as used in the present description means: a compound that upon activation forms the active metal catalyst.

“metallocene” as used in the present description means: a metal catalyst or metal catalyst precursor typically consisting of two substituted cyclopentadienyl (Cp) ligands bound to a metal active site.

“transition metal” as used in the present description means: a metal from any of the Groups 3-10 of the IUPAC Periodic Table of elements or in other words a Group 3 metal, a Group 4 metal, a Group 5 metal, a Group 6 metal, a Group 7 metal, a Group 8 metal, a Group 9 metal or a Group 10 metal.

“Group 3 metal” as used in the present description means: a metal selected from Group 3 of the IUPAC Periodic Table of elements, being scandium (Sc), yttrium (Y), lanthanum (La) and other lanthanides (Ce—Lu), and actinium (Ac) and other actinides (Th—Lr).

“Group 4 metal” as used in the present description means: a metal selected from Group 4 of the IUPAC Periodic Table of elements, being titanium (Ti), zirconium (Zr) and hafnium (Hf).

“Group 5 metal” as used in the present description means: a metal selected from Group 5 of the IUPAC Periodic Table of elements, being vanadium (V), niobium (Nb) and tantalum (Ta).

“Group 6 metal” as used in the present description means: a metal selected from Group 6 of the Periodic Table of elements, being chromium (Cr), molybdenum (Mo) and tungsten (W).

“Group 7 metal” as used in the present description means: a metal selected from Group 7 of the Periodic Table of elements, being manganese (Mn), technetium (Tc) and rhenium (Re).

“Group 8 metal” as used in the present description means: a metal selected from Group 8 of the Periodic Table of elements, being iron (Fe), ruthenium (Ru) and osmium (Os).

“Group 9 metal” as used in the present description means: a metal selected from Group 9 of the Periodic Table of elements, being cobalt (Co), rhodium (Rh) and iridium (Ir).

“Group 10 metal” as used in the present description means: a metal selected from Group 10 of the Periodic Table of elements, being nickel (Ni), palladium (Pd) and platinum (Pt).

“main group metal” as used in the present description means: a metal that is an element of Groups 1, 2, and 13-15 of the period table. In other words, metals of:

-   -   Group 1: lithium (Li), sodium (Na), and potassium (K)     -   Group 2: beryllium (Be), magnesium (Mg), and calcium (Ca)     -   Group 13: boron (B), aluminum (Al), gallium (Ga), and indium         (In)     -   Group 14: germanium (Ge), and tin (Sn)     -   Group 15: antimony (Sb), and bismuth (Bi)

main group metals also include for the context of the present invention zinc (Zn), of the IUPAC Periodic Table of elements.

“co-catalyst” as used in the present description means: a compound that activates the metal catalyst precursor to obtain the active metal catalyst. In the present description these two terms are used interchangeable.

“oxidizing agent” as used in the present description means: an agent or a reagent that is suitable for functionalizing main group metal-functionalized first polyolefin block by oxidizing the bond between the main group metal center and the polyolefin.

“methylaluminoxane” or “MAO” as used in the present description means: a compound derived from the partial hydrolysis of trimethyl aluminum that serves as a co-catalyst for catalytic olefin polymerization.

“SMAO” as used in the present description means: supported methylaluminoxane, viz. a methylaluminoxane bound to a solid support.

“DMAO” as used in the present description means: depleted methylaluminoxane, viz. a methylaluminoxane from which the free trimethyl aluminum has been removed.

“MMAO” as used in the present description means: modified methylaluminoxane, viz. the product obtained after partial hydrolysis of trimethyl aluminum plus another trialkyl aluminum such as tri(i-butyl) aluminum or tri-n-octyl aluminum.

“fluorinated aryl borate or fluorinated aryl borane” as used in the present description means: a borate compound having three or four fluorinated (preferably perfluorinated) aryl ligands or a borane compound having three fluorinated (preferably perfluorinated) aryl ligands.

“halide” as used in the present description means: an ion selected from the group of: fluoride (F⁻), chloride (Cl⁻), bromide (Br⁻) or iodide (I⁻).

“halogen” as used in the present description means: an atom selected from the group of: fluorine (F), chlorine (Cl), bromine (Br) or iodine (I).

“heteroatom” as used in the present description means: an atom other than carbon or hydrogen. Heteroatom also includes halides.

“heteroatom selected from Group 14, 15, 16 or 17 of the IUPAC Periodic Table of the Elements” as used in the present description means: a hetero atom selected from Si, Ge, Sn [Group 14], N, P, As, Sb, Bi [Group 15], O, S, Se, Te [Group 16], F, Cl, Br, I [Group 17].

“alkyl” as used in the present description means: a group consisting of carbon and hydrogen atoms having only single carbon-carbon bonds. An alkyl group may be straight or branched, un-substituted or substituted. It may contain aryl substituents. It may or may not contain one or more heteroatoms, such as oxygen (O), nitrogen (N), phosphorus (P), silicon (Si), tin (Sn) or sulfur (S) or halogen (i.e. F, Cl, Br, I).

“aryl” as used in the present description means: a substituent derived from an aromatic ring. An aryl group may or may not contain one or more heteroatoms, such as oxygen (O), nitrogen (N), phosphorus (P), silicon (Si), tin (Sn), sulfur (S) or halogen (i.e. F, Cl, Br, I). An aryl group also encloses substituted aryl groups wherein one or more hydrogen atoms on the aromatic ring have been replaced by hydrocarbyl groups.

“alkoxide” or “alkoxy” as used in the present description means: a substituent obtained by deprotonation of an aliphatic alcohol. It consists of an alkyl group bonded to an oxygen atom.

“aryloxide” or “aryloxy” or “phenoxide” as used in the present description means: a substituent obtained by deprotonation of an aromatic alcohol. It consists of an aryl group bonded to an oxygen atom.

“silyl group” as used in the present description means: a linear, branched or cyclic substituent containing 1-20 silicon atoms. Said silyl group may comprise Si—Si single or double bonds.

Expressions like for example “C1-C20” and similar formulations may refer to a range regarding a number of carbon atoms, here for example from 1 to 20 carbon atoms.

SHORT DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing of the structures of the oxidizing agents.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to the novel and inventive cascade-like process for the preparation of block copolymers having a first polyolefin block and at least one second polymer block and the products obtained therefrom.

The key of the present invention is that a process is provided for the production of block copolymers having a reduced number of process steps compared to the classical approaches.

The process according to the present invention comprises at least three process steps, viz. steps A), B) and C).

Step A) is related to polymerizing at least one type of olefin monomer using a catalyst system to obtain a first polyolefin block containing a main group metal on at least one chain end. In other words, a main group metal-functionalized first polyolefin block is obtained in step A). Said main group metal is derived from the at least one type of chain transfer agent. The growing polymer chain resides at least partially on the main group metal center of the chain transfer agent.

This is considered to be the main product of step A), this is an intermediate product in the process according to the present invention. The growing polymer chain residing on the main group metal center of the chain transfer agent is attached on at least one of its sides to a main group metal.

The catalyst system used in step A) comprises: i) a Group 3-10, preferably a Group 3-8, metal catalyst or metal catalyst precursor; ii) at least one type of chain transfer agents; and iii) optionally a co-catalyst.

Step B) relates to reacting the intermediate product obtained in step A) with at least one type of oxidizing agent to obtain a main group metal-functionalized oxidized first polyolefin block, being a first polyolefin block having at least one oxidized chain end attached to a main group metal function. During step B) the grown polymer chain attached to the main group metal is oxidized at the position where it is attached to said metal. The main group metal-functionalized oxidized first polyolefin block can thus be used as catalytic initiator in step C).

Step C) relates to forming at least one second polymer block attached to the oxidized first polyolefin block obtained in step B). Said oxidized first polyolefin block of step B) consists of a polyolefin containing a functional group on at least one chain end in order to obtain the block copolymer. When both ends are oxidized a triblock copolymer is obtained and when one of the chain ends are oxidized, a diblock copolymer is obtained.

There are several synthetic routes according to the present invention in which the second polymer block may be formed during step C). It may for example be grown via ROP or it may be added via nucleophilic substitution.

In an embodiment, step C) relates to obtaining a block copolymer and is carried out by ROP using at least one type of cyclic monomer, wherein as a catalytic initiator at least one main group metal-functionalized oxidized chain end of the first polyolefin block obtained in step B) is used. More details about ROP are provided below.

In an embodiment, step C) relates to obtaining a block copolymer and is carried out by a nucleophilic substitution reaction, for example especially a transesterification, at a carbonyl group-containing functionality, for example especially a carboxylic or carbonic acid ester functionality, of at least one second polymer wherein as an initiator at least one oxidized chain end of the first polyolefin block obtained in step B) is used. More details about nucleophilic substitution are provided below.

In an embodiment, step C) relates to obtaining a block copolymer and is carried out by a combination of ROP and nucleophilic substitution, wherein as an initiator at least one oxidized chain end of the first polyolefin block obtained in step B) is used.

Preferably, said all process steps are carried out directly one after another. Preferably, the process steps A), B), and C) can be carried out for example without hydrolysis and/or intermediate workup. Preferably, the process is carried out in a series of reactors.

Each of these steps will be discussed in more detail below and embodiments are discussed below.

Step A): Preparation of First Polyolefin Block

The first step in the process according to the present invention is the preparation of a polyolefin that has a reactive electrophilic metal end group. During the polymerization reaction a chain transfer agent, more precisely a main group metal hydrocarbyl or main group metal hydride chain transfer agent (being a main group metal atom bearing one or more hydrocarbyl and/or hydride groups) is used. The product obtained in step A) is then a main group metal-functionalized first polyolefin block (being a polyolefin that is functionalized on at least one of its ends with a main group metal).

Since the present method is related to the preparation of a block copolymer, at least a second polymer block is to be formed and that is why the polyolefin obtained in step A) is denoted as a “first polyolefin block”.

From the prior art chain transfer reactions are known using several different chain transfer agents and using several catalyst systems.

The requirements for this chain transfer polymerization are the presence of i) at least one type of olefin, ii) at least one type of chain transfer agent; iii) at least one type of metal catalyst or metal catalyst precursor. Each of these will be discussed separately below.

Olefins Suitable For Use in Step A)

Examples of suitable monomers include straight-chain or branched α-olefins. Said olefins preferably have between 2 and 30 carbon atoms, more preferably between 2 and 20 carbon atoms. A non-limiting list of examples of olefins is provided above. Preferably, one or more of the following are used: ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-cyclopentene, cyclohexene, norbornene, ethylidene-norbornene, and vinylidene-norbornene and one or more combinations thereof. In addition, a combination of ethylene and/or propylene on the one and one or more other olefins on the other hand is also possible. Substituted analogues of the monomers discussed above may also be used, e.g. substituted by one or more halogens. Also aromatic monomers can be used according to the present invention. It is also possible to use a combination of two or more olefins, such as a combination of ethylene with α-olefins to arrive at an LLDPE-block.

Chain Transfer Agent Suitable For Use in step A)

From the prior art chain transfer reactions are known using several different chain transfer agents.

Chain transfer to aluminum alkyls, zinc alkyls, and boron alkyls and boron hydrides as such has been reported. The present invention uses main group metal hydrocarbyls and/or main group metal hydrides as chain transfer agents.

As non-limiting examples of a main group metal hydrocarbyl or main group metal hydride the following can be used: one or more hydrocarbyl or hydride groups attached to a main group metal selected from aluminum, magnesium, calcium, zinc, gallium or boron. Of these several specific examples are specified below.

The chain transfer agent may be selected from the group specified above having a general structure: R_(p−q)M(p)X_(q) wherein M is a main group metal, R is a hydride or hydrocarbyl group, p is the oxidation state of the metal, X is a heteroatom or heteroatom-bonded ligand, and q is an integer between 0 and p−1. At least one hydrocarbyl or hydride group should be present. Preferably, at least one R group is alkyl.

When R is an alkyl this group has up to and including 30 carbon atoms, such as up to and including 20 carbon atoms, preferably up to and including 10 carbon atoms, such as methyl, ethyl, propyl, butyl, heptyl, hexyl, septyl, octyl, nonyl or decyl and can be unbranched or branched.

When R is an alkenyl this group has up to and including 30 carbon atoms, such as up to and including 20 carbon atoms, preferably up to and including 10 carbon atoms, such as ethenyl, propenyl, butenyl, heptenyl, hexenyl, septenyl, octenyl, nonenyl or decenyl and can be unbranched or branched.

When R is an alkynyl this group has up to and including 30 carbon atoms, such as up to and including 20 carbon atoms, preferably up to and including 10 carbon atoms, such as vinyl, propynyl, butynyl, heptynyl, hexynyl, septynyl, octynyl, nonynyl or decynyl and can be unbranched or branched.

When R is aryl it can be selected from monocyclic or bicyclic groups or groups having more than two rings. These rings may be fused together or linked by a spacer. The aryl might be substituted on any ring position with a hydrocarbyl or heteroatom-containing group. Examples of aryl moieties include, but are not limited to, chemical structures such as phenyl, 1-naphthyl, 2-naphthyl, dihydronaphthyl, tetrahydronaphthyl, biphenyl, anthryl, phenanthryl, biphenylenyl, acenaphthenyl, acenaphthylenyl, tolyl, xylyl, mesityl, 2-methoxy-phenyl, 2,6-dimethoxy-phenyl, 2-N,N-dimethylaminomethyl-phenyl, 2-N,N-dimethylamino-phenyl.

When R is an aryl-substituted alkyl this group consists of an alkyl containing an aryl that might be substituted on any ring position with a hydrocarbyl. Non-limiting examples are: benzyl, 1-phenylethyl, 2-phenylethyl, diphenylmethyl, 3-phenylpropyl, and 2-phenylpropyl, o-methoxy-phenyl-methyl, o-N,N-dimethylamino-phenyl-methyl.

In an embodiment main group metal hydrocarbyls containing hydrocarbyldiyl groups, e.g. cyclic or oligomeric main group metal hydrocarbyls or alkoxyhydrocarbyl or amidohydrocarbyl groups may be used in order to obtain telechelic first polymer blocks, which can be used to prepare triblock copolymers. Examples of such cyclic or oligomeric chain transfer agents are EtZn[CH₂CH(Et)(CH₂)₆CH(Et)CH₂Zn]_(n)Et (n=1, 2, 3, . . . ), iBu₂Al(CH₂)₆OAliBu₂, iBu₂Al(CH₂)₂₀OAliBu₂, Al[(CH₂)₂₀OAliBu₂]₃, iBu₂Al(CH₂)₂₀N(Me)AliBu₂, iBu₂Al(CH₂)₆N(Me)AliBu₂, Al[(CH₂)20N(Me)AliBu₂]₃ as exemplified in Makio et al. J. Am. Chem. SOC. 2013, (135), 8177-8180 and WO 2011/014533.

The heteroatom-containing ligand X can be selected from the group consisting of: halide, oxide (—O—), carboxylate (—O₂CR⁴⁰), alkoxide (—OR⁴⁰; i.e. O-alkyl), aryloxide (—OAr), thiolate (—SR⁴⁰), amide (—NR⁴⁰R⁴¹), phosphide (—PR⁴⁰R⁴¹), mercaptanate (—SAr), siloxide (—OSiR⁴⁰R⁴¹R⁴²), stannate (—OSnR⁴⁰R⁴¹R⁴²). Wherein R⁴⁰, R⁴¹, R⁴² are each independently a hydrocarbyl.

In an embodiment, said chain transfer agent may be selected from tri(i-butyl) aluminum, trimethyl aluminum, triethyl aluminum, tri(i-propyl) aluminum (TIBA), tri(n-butyl) aluminum, tri(t-butyl) aluminum, tri(n-hexyl) aluminum, tri(n-octyl) aluminum, di(i-butyl) aluminum hydride (DIBALH), dimethyl aluminum 2,6-di(t-butyl)-4-methyl-phenoxide, diethyl aluminum 2,6-di(t-butyl)-4-methyl-phenoxide, di(i-butyl) aluminum 2,6-di(t-butyl)-4-methyl-phenoxide, i-butyl aluminum-bis(di-trimethylsilyl)amide), n-octyl aluminum-di(pyridine-2-methoxide), bis(n-octadecyl)-i-butyl aluminum, i-butyl aluminum-bis(di(n-pentyl)amide), n-octyl aluminum-bis(2,6-di-t-butylphenoxide), n-octyl aluminum-di-ethyl(1-naphthyl)amide), ethyl aluminum-bis(t-butyldimethylsiloxide), ethyl aluminum-di(bis(trimethylsilyl)amide), ethyl aluminum-bis(2,3,6,7-dibenzo-1-azacycloheptane-amide), n-octyl aluminum-bis(2,3,6,7-dibenzo-1-azacycloheptane-amide), n-octyl-aluminum-bis(dimethyl(t-butyl)siloxide, trimethyl gallium, triethyl gallium, tri(i-butyl) gallium, di-n-butyl magnesium (DBM), dimethyl magnesium, butyl-octyl-magnesium, butyl-ethyl-magnesium, butyl magnesium 2,6-di(t-butyl)-4-methyl-phenoxide, benzyl calcium 2,6-di(t-butyl)-4-methyl-phenoxide, diethyl zinc, dimethyl zinc, di(i-propyl) zinc, di-t-butyl zinc, di-(n-hexyl) zinc, ethyl zinc (t-butoxide), methyl zinc 2,6-di(t-butyl)-4-methyl-phenoxide, ethyl zinc 2,6-di(t-butyl)-4-methyl-phenoxide, trimethyl boron, trimethyl boron, tributyl boron, diethyl boron 2,6-di(t-butyl)-4-methyl-phenoxide, 9-borabicyclo(3.3.1)nonane, catecholborane, diborane.

Using a chain transfer agent undergoing reversible transfer reactions or a chain shuttling agent can lead to a living-like polymerization. For example hydrocarbyl zinc can be used as an reversible chain transfer agent and/or chain shuttling agent together with another main group metal hydrocarbyl chain transfer agent. An example of the later could be using a combination of for example zinc hydrocarbyl and an aluminum hydrocarbyl as the chain transfer agents, a ternary system (TM+Al+Zn, where TM is transition metal of the catalyst) is formed. Doing so can lead to reversible transfer reactions.

Alternatively hydrocarbyl aluminum, hydrocarbyl gallium, hydrocarbyl boron or hydrocarbyl calcium can be used instead of hydrocarbyl zinc.

In an embodiment, the chain transfer agent is selected from the group consisting of TIBA, DIBALH, DBM and DEZ.

Catalyst System Suitable For Use in Step A)

A catalyst system for use in step a) comprises the following components:

-   -   i) a metal catalyst or metal catalyst precursor comprising a         metal from Group 3-10 of the IUPAC Periodic Table of elements;         and     -   ii) at least one type of chain transfer agent; and     -   iii) optionally a co-catalyst.

Suitable chain transfer agents have been discussed above. Suitable metal catalyst and/or metal catalyst precursors are discussed in this section as well as suitable co-catalysts, which are optional. When during step A) a metal catalyst is used, the co-catalyst is optional. When during step A) a metal catalyst precursor is used, a co-catalyst is required to obtain an active metal catalyst.

Metal Catalyst or Metal Catalyst Precursor Suitable For step A)

In the section below several examples for metal catalysts or metal catalyst precursors, which may be used to prepare the metal catalyst according to the present invention, are specified. Metal catalysts that are suitable for use in step A) of the present invention may be obtained by reacting the metal catalyst precursors with a co-catalyst either prior to use in step A) or by in situ reaction with a co-catalyst.

According to the present invention, the metal catalyst has a metal center selected from a Group 3 metal, a Group 4 metal, a Group 5 metal, a Group 6 metal, a Group 7 metal, a Group 8 metal, a Group 9 metal or a Group 10 metal, preferably Y, Ti, Zr, Hf, V, Cr, Fe, Co, Ni, Pd.

The metal catalysts or metal catalyst precursors may for example be a C_(s)-, C₁- or C₂-symmetric zirconium or hafnium metallocene, preferably an indenyl substituted zirconium or hafnium dihalide, more preferably a bridged bis-indenyl zirconium or hafnium dihalide, even more preferably rac-dimethylsilyl bis-indenyl zirconium or hafnium dichloride (rac-Me₂Si(Ind)₂ZrCl₂ and rac-Me₂Si(Ind)₂HfCl₂, respectively), or rac-dimethylsilyl bis-(2-methyl-4-phenyl-indenyl) zirconium or hafnium dichloride (rac-Me₂Si(2-Me-4-Ph-Ind)₂ZrCl₂ and rac-Me₂Si(2-Me-4-Ph-Ind)₂HfCl₂, respectively).

According to the invention, said catalyst precursor can be for example a so-called half-metallocene, or constrained geometry catalyst, even more preferably, C₅Me₅[(C₆H₁₁)₃P═N]TiCl₂, [Me₂Si(C₅Me₄)N(tBu)]TiCl₂, [C₅Me₄(CH₂CH₂NMe₂]TiCl₂.

According to the invention, said catalyst can be for example a so-called post-metallocene, preferably [Et₂NC(N(2,6-iPr₂-C₆H₃)]TiCl₃ or [N-(2,6-di(l-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium dimethyl.

The metal catalyst or metal catalyst precursor can also be for example a preferably C_(s) or C₁ symmetric compound according to the formula (C₅R⁸ ₄)R⁹(C₁₃R⁸8)ML¹ _(n), where C₅R⁸ ₄ is an unsubstituted or substituted cyclopentadienyl, and C₁₃R¹¹ ₈ is an unsubstituted fluorenyl group or a substituted fluorenyl group; and the bridging R⁹ group is selected from the group consisting of —Si(Me)₂-, —Si(Ph)₂-, —C(Me)₂- or —C(Ph)₂-, thus producing C₁- and C_(s)-symmetric metallocenes.

Non-limiting examples of zirconocene dichloride metal catalyst precursors suitable for use in the present invention include: bis(cyclopentadienyl) zirconium dichloride, bis(methyl-cyclopentadienyl) zirconium dichloride, bis(n-propyl-cyclopentadienyl) zirconium dichloride, bis(n-butyl-cyclopentadienyl) zirconium dichloride, bis(1,3-dimethyl-cyclopentadienyl) zirconium dichloride, bis(1,3-di-t-butyl-cyclopentadienyl) zirconium dichloride, bis(1,3-ditrimethylsilyl-cyclopentadienyl) zirconium dichloride, bis(1,2,4-trimethyl-cyclopentadienyl) zirconium dichloride, bis(1,2,3,4-tetramethyl-cyclopentadienyl) zirconium dichloride, bis(pentamethylcyclopentadienyl) zirconium dichloride, bis(indenyl) zirconium dichloride, bis(2-phenyl-indenyl) zirconium dichloride, bis(fluorenyl) zirconium dichloride, bis(tetrahydrofluorenyl) zirconium dichloride, dimethylsilyl-bis(cyclopentadienyl) zirconium dichloride, dimethylsilyl-bis(3-t-butyl-cyclopentadienyl) zirconium dichloride, dimethylsilyl-bis(3-trimethylsilyl-cyclopentadienyl) zirconium dichloride, dimethylsilyl-bis(tetrahydrofluorenyl) zirconium dichloride, dimethylsilyl-(1-indenyl)(cyclopentadienyl) zirconium dichloride, dimethylsilyl-(1-indenyl)(fluorenyl) zirconium dichloride, dimethylsilyl-(1-indenyl)(octahydrofluorenyl) zirconium dichloride, rac-dimethylsilyl-bis(2-methyl-3-t-butyl-cyclopentadienyl) zirconium dichloride, rac-dimethylsilyl-bis(1-indenyl) zirconium dichloride, rac-dimethylsilyl-bis(4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, rac-dimethylsilyl-bis(2-methyl-1-indenyl) zirconium dichloride, rac-dimethylsilyl-bis(4-phenyl-1-indenyl) zirconium dichloride, rac-dimethylsilyl-bis(2-methyl-4-phenyl-1-indenyl) zirconium dichloride, rac-ethylene-bis(1-indenyl) zirconium dichloride, rac-ethylene-bis(4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, rac-1,1,2,2-tetramethylsilanylene-bis(1-indenyl) zirconium dichloride, rac-1,1,2,2-tetramethylsilanylene-bis(4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride, rac-ethylidene(1-indenyl)(2,3,4,5-tetramethyl-1-cyclopentadienyl) zirconium dichloride, rac-[1-(9-fluorenyl)-2-(2-methylbenzo[b]indeno[4,5-d]thiophen-1-yl)ethane]zirconium dichloride, dimethylsilyl bis(cyclopenta-phenanthren-3-ylidene) zirconium dichloride, dimethylsilyl bis(cyclopenta-phenanthren-1-ylidene) zirconium dichloride, dimethylsilyl bis(2-methyl-cyclopenta-phenanthren-1-ylidene) zirconium dichloride, dimethylsilyl bis(2-methyl-3-benz-inden-3-ylidene) zirconium dichloride, dimethylsilyl-bis[(3a,4,5,6,6a)-2,5-dimethyl-3-(2-methylphenyl)-6H-cyclopentathien-6-ylidene] zirconium dichloride, dimethylsilyl-(2,5-dimethyl-1-phenylcyclopenta[b]pyrrol-4(1H)-ylidene)(2-methyl-4-phenyl-1-indenyl) zirconium dichloride, bis(2-methyl-1-cyclopenta-phenanthren-1-yl)zirconium dichloride, [ortho-bis(4-phenyl-2-indenyl) benzene] zirconium dichloride, [ortho-bis(5-phenyl-2-indenyl) benzene] zirconium dichloride, [ortho-bis(2-indenyl)benzene] zirconium dichloride, [ortho-bis (1-methyl-2-indenyl)benzene] zirconium dichloride, [2,2′-(1,2-phenyldiyl)-1,I′dimethylsilyl-bis(indenyl)] zirconium dichloride, [2,2′-(1,2-phenyldiyl)-1,1′-(1,2-ethanediyl)-bis(indenyl)] zirconium dichloride, dimethylsilyl-(cyclopentadienyl)(9-fluorenyl) zirconium dichloride, diphenylsilyl-(cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(cyclopentadienyl)(fluorenyl) zirconium dichloride, diphenylmethylene-(cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(cyclopentadienyl)(octahydrofluorenyl) zirconium dichloride, diphenylmethylene-(cyclopentadienyl)(octahydrofluorenyl) zirconium dichloride, dimethylmethylene-(cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, diphenylmethylene-(cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, dimethylmethylene-(3-methyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, diphenylmethylene-(3-methyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(3-cyclohexyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, diphenylmethylene-(3-cyclohexyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(3-t-butyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, diphenylmethylene-(3-t-butyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(3-ademantyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, diphenylmethylene-(3-ademantyl-1-cyclopentadienyl)(fluorenyl) zirconium dichloride, dimethylmethylene-(3-methyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, diphenylmethylene-(3-methyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, dimethylmethylene-(3-cyclohexyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, diphenylmethylene-(3-cyclohexyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, dimethylmethylene-(3-t-butyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, diphenylmethylene-(3-t-butyl-1-cyclopentadienyl)(2,7-di-t-butyl-fluorenyl) zirconium dichloride, dimethylmethylene-(3-methyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, diphenylmethylene-(3-methyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, dimethylmethylene-(3-cyclohexyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, diphenylmethylene-(3-cyclohexyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, dimethylmethylene-(3-t-butyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, diphenylmethylene-(3-t-butyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, dimethylmethylene-(3-ademantyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride, diphenylmethylene-(3-ademantyl-cyclopentadienyl)(octahydro-octamethyl-dibenzo-fluorenyl) zirconium dichloride.

In a preferred embodiment, the metal catalyst or metal catalyst precursor can be for example: [[2,2′-[[[2-(dimethylamino-κN)ethyl]imino-κN]bis(methylene)]bis[4,6-bis(1,1-dimethylethyl) phenolato-κO]] zirconium dibenzyl, (phenylmethyl)[[2,2′-[(propylimino-κN)bis(methylene)]bis[4,6-bis(1,1-dimethylethyl)phenolato-κO]] zirconium dibenzyl or (phenylmethyl)[[2,2′-[[[(2-pyridinyl-κN)methyl]imino-κN]bis(methylene)]bis[4,6-bis(1,1-dimethylethyl)phenolato-κO]] zirconium dibenzyl.

In a preferred embodiment, complexes as reported in WO 00/43426, WO 2004/081064, US 2014/0039138 A1, US 2014/0039139 A1 and US 2014/0039140 A1 are suitable to use as metal catalyst precursors for the processes of the present invention.

Compounds analogous to those listed above but where Zr has been replaced by Hf, so called hafnocenes, may also be used according to the as catalyst precursors present invention.

The metal catalysts or metal catalyst precursors for use in the present invention may also be from post-metallocene catalysts or catalyst precursors.

In a preferred embodiment, the metal catalyst or metal catalyst precursor may be: [HN(CH2CH2N-2,4,6-Me3-C6H2)2]Hf(CH2Ph)2 or bis[N,N′-(2,4,6-trimethylphenyl)amido)ethylenediamine]hafnium dibenzyl.

In a another preferred embodiment, the metal catalyst or metal catalyst precursor may be 2,6-diisopropylphenyl-N-(2-methyl-3-(octylimino)butan-2) hafnium trimethyl, 2,4,6-trimethylphenyl-N-(2-methyl-3-(octylimino)butan-2) hafnium trimethyl.

In a preferred embodiment, the metal catalyst or metal catalyst precursor may be [2,6-iPr2C6H3NC(2-iPr-C6H4)-2-(6-C5H6)]HfMe2-[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl) (□-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium dimethyl.

Other non-limiting examples of metal catalyst precursors according to the present invention are: [N-(2,6-di(1-methylethyl)phenyl)amido)(o-tolyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)] hafnium dimethyl, [N-(2,6-di(1-methylethyl)phenyl)amido)(o-tolyl)(α,α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)] hafnium di(N,N-dimethylamido), [N-(2,6-di(l-methylethyl)phenyl)amido)(o-tolyl)(α,α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)] hafnium dichloride, [N-(2,6-di(1-methylethyl)phenyl)amido)(phenanthren-5-yl)(α,α-naphthalen-2-diyl (6-pyridin-2-diyl)methane)] hafnium dimethyl, [N-(2,6-di(1-methylethyl)phenyl)amido)(phenanthren-5-yl)(α-naphthalen-2-diyl(6-pyridin 2-diyl)methane)] hafnium di(N,N-dimethylamido), [N-(2,6-di(l-methylethyl)phenyl)amido)(phenanthren-5-yl) (α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)] hafnium dichloride. Other non-limiting examples include the family of pyridyl diamide metal dichloride complexes such as: [N-[2,6-bis(1-methylethyl)phenyl]-6-[2-[phenyl(phenylamino-κN)methyl]phenyl]-2-pyridinemethanaminato(2)-κN1,κN2]hafnium dichloride, [N-[2,6-bis(1-methylethyl)phenyl]-6-[2-[(phenylamino-κN)methyl]-1-naphthalenyl]-2-pyridinemethanaminato(2-)-κN1,κN2] hafnium dichloride, [N-[2,6-bis(1-methylethyl)phenyl]-α-[2-(1-methylethyl)phenyl]-6-[2-[(phenylamino-κN)methyl]phenyl]-2-pyridinemethanaminato(2-)-κN1,κN2] hafnium dichloride, [N-(2,6-diethylphenyl)-6-[2-[phenyl(phenylamino-κN)methyl]-1-naphthalenyl]-2-pyridinemethanaminato(2-)-κN1,κN2]zirconium dichloride, [4-methyl-2-[[2-phenyl-1-(2-pyridinyl-κN)ethyl]amino-κN]phenolato(2-)-κO]bis(phenylmethyl)hafnium bis(phenylmethyl), [2-(1,1-dimethylethyl)-4-methyl-6-[[2-phenyl-1-(2-pyridinyl-κN)ethyl]amino-κN]phenolato(2-)-κO] hafnium bis(phenylmethyl), [2-(1,1-dimethylethyl)-4-methyl-6-[[phenyl(2-pyridinyl-κN)methyl]amino-κN]phenolato(2-)-κO]hafnium bis(phenylmethyl).

Non-limiting examples of titanium dichloride metal catalyst precursors suitable for use in the present invention include: cyclopentadienyl(P,P,P-tri-t-butylphosphine imidato) titanium dichloride, pentafluorophenylcyclopentadienyl(P,P,P-tri-t-butylphosphine imidato) titanium dichloride, pentamethylcyclopentadienyl(P,P,P-tri-t-butylphosphine imidato) titanium dichloride, 1,2,3,4-tetraphenyl-cyclopentadienyl(P,P,P-tri-t-butylphosphine imidato) titanium dichloride, cyclopentadienyl(P,P,P-tricyclohexylphosphine imidato) titanium dichloride, pentafluorophenyl cyclopentadienyl(P,P,P-tricyclohexylphosphine imidato) titanium dichloride, pentamethylcyclopentadienyl(P,P,P-tricyclohexylphosphine imidato) titanium dichloride, 1,2,3,4-tetraphenyl-cyclopentadienyl(P,P,P-tricyclohexylphosphine imidato) titanium dichloride, pentamethylcyclopentadienyl(P,P-dicyclohexyl-P-(phenylmethyl)phosphine imidato) titanium dichloride, cyclopentadienyl(2,6-di-t-butyl-4-methylphenoxy) titanium dichloride, pentafluorophenylcyclopentadienyl(2,6-di-t-butyl-4-methylphenoxy) titanium dichloride, pentamethylcyclopentadienyl(2,6-di-t-butyl-4-methylphenoxy) titanium dichloride, 1,2,3-trimethyl-cyclopentadienyl(2,6-bis(1-methylethyl)phenolato) titanium dichloride, [(3a,4,5,6,6a-η)-2,3,4,5,6-pentamethyl-3aH-cyclopenta[b]thien-3a-yl](2,6-bis(1-methylethyl)phenolato) titanium dichloride, pentamethylcyclopentadienyl(N,N′-bis(1-methylethyl)ethanimidamidato) titanium dichloride, pentamethylcyclopentadienyl(N, N′-dicyclohexylbenzenecarboximidamidato) titanium dichloride, pentamethylcyclopentadienyl(N,N′-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, cyclopentadienyl(1,3-bis(1,1-dimethylethyl)-2-imidazolidiniminato) titanium dichloride, cyclopentadienyl(1,3-dicyclohexyl-2-imidazolidiniminato) titanium dichloride, cyclopentadienyl(1,3-bis[2,6-bis(1-methylethyl)phenyl]-2-imidazolidiniminato) titanium dichloride, pentafluorophenylcyclopentadienyl(1,3-bis(1,1-dimethylethyl)-2-imidazolidiniminato) titanium dichloride, pentafluorophenylcyclopentadienyl(1,3-dicyclohexyl-2-imidazolidiniminato) titanium dichloride, pentafluorophenylcyclopentadienyl(1,3-bis[2,6-bis(1-methylethyl)phenyl]-2-imidazolidiniminato) titanium dichloride, pentamethylcyclopentadienyl(di-t-butylketimino) titanium dichloride, pentamethylcyclopentadienyl(2,2,4,4-tetramethyl-3-pentaniminato) titanium dichloride, [(3a,4,5,6,6a-η)-2,4,5,6-tetramethyl-3aH-cyclopenta[b]thien-3a-yl](2,2,4,4-tetramethyl-3-pentaniminato) titanium dichloride, cyclopentadienyl(N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, pentafluorophenylcyclopentadienyl(N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, pentamethylcyclopentadienyl(N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, cyclopentadienyl(2,6-difluoro-N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, pentafluorophenylcyclopentadienyl(2,6-difluoro-N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, pentamethylcyclopentadienyl(2,6-difluoro-N,N-bis(1-methylethyl)benzenecarboximidamidato) titanium dichloride, cyclopentadienyl(N,N-dicyclohexyl-2,6-difluorobenzenecarboximidamidato) titanium dichloride, pentafluorophenylcyclopentadienyl(N,N-dicyclohexyl-2,6-difluorobenzenecarboximidamidato) titanium dichloride, pentamethylcyclopentadienyl(N,N-dicyclohexyl-2,6-difluorobenzenecarboximidamidato) titanium dichloride, cyclopentadienyl(N,N,N′,N′-tetramethylguanidinato) titanium dichloride, pentafluorophenylcyclopentadienyl(N,N,N′,N′-tetramethylguanidinato) titanium dichloride, pentamethylcyclopentadienyl(N,N,N′,N′-tetramethylguanidinato) titanium dichloride, pentamethylcyclopentadienyl(1-(imino)phenylmethyl)piperidinato) titanium dichloride, pentamethylcyclopentadienyl chromium dichloride tetrahydrofuran complex.

Non-limiting examples of titanium (IV) dichloride metal catalyst suitable for use in the present invention are: (N-t-butylamido)(dimethyl)(tetramethylcyclopentadienyl)silane titanium dichloride, (N phenylamido)(dimethyl)(tetramethylcyclopentadienyl) silane titanium dichloride, (N sec-butylamido)(dimethyl)(tetramethylcyclopentadienyl)silane titanium dichloride, (N sec-dodecylamido) (dimethyl)(fluorenyl)silane titanium dichloride, (3 phenylcyclopentadien-1-yl) dimethyl(t-butylamido) silane titanium dichloride, (3 (pyrrol-l-yl)cyclopentadien-1-yl) dimethyl(t-butylamido)silane titanium dichloride, (3,4-diphenylcyclopentadien-1-yl)dimethyl(t-butylamido) silane titanium dichloride, 3 (3-N,N-dimethylamino)phenyl) cyclopentadien-1-yl)dimethyl(t-butylamido) silane titanium dichloride, (P-t-butylphospho)(dimethyl) (tetramethylcyclopentadienyl) silane titanium dichloride. Other examples are the metal catalyst precursor cited in the list directly above wherein Ln is dimethyl, dibenzyl, diphenyl, 1,4-diphenyl-2-butene-1,4-diyl, 1,4-dimethyl-2-butene-1,4-diyl or 2,3-dimethyl-2-butene-1,4-diyl.

Suitable metal catalyst precursors can be also the trivalent transition metal as those described in WO 9319104 (for example see especially example 1, page 13, line 15).

Suitable metal catalyst precursors can be also the trivalent transition metal as [C5Me4CH2CH2N(n-Bu)2]TiCl2 described in WO 9613529 (for example see especially example III, page 20, line 10-13) or [C5H(iPr)3CH2CH2NMe2]TiCl2 described in WO 97142232 and WO 9742236 (for example see especially example 1, page 26, line 14).

In an embodiment, the metal catalyst precursor is [C5H4CH2CH2NMe2]TiCl2;

In an embodiment, the metal catalyst or metal catalyst precursor may also be [C5Me4CH2CH2NMe2]TiCl2, [C5H4CH2CH2NiPr2]TiCl2, [C5Me4CH2CH2NiPr2]TiCl2, [C5H4C9H6N]TiCl2, [C5H4CH2CH2NMe2]CrCl2, [C5Me4CH2CH2NMe2]CrCl2; [C5H4CH2CH2NiPr2]CrCl2, [C5Me4CH2CH2NiPr2]CrCl2 or [C5H4C9H6N]CrCl2.

A non-limiting list of examples of metal catalyst precursors that would be suitable according to the present invention are: (N,N dimethylamino)methyl-tetramethylcyclopentadienyl titanium dichloride, (N,N dimethylamino)ethyl-tetramethylcyclopentadienyl titanium dichloride, (N,N dimethylamino)propyl-tetramethylcyclopentadienyl titanium dichloride, (N,N dibutylamino)ethyl-tetramethylcyclopentadienyl titanium dichloride, (pyrrolidinyl)ethyl-tetramethylcyclopentadienyl titanium dichloride, (N,N-dimethylamino)ethyl-fluorenyl titanium dichloride, (bis(1-methyl-ethyl)phosphino)ethyl-tetramethylcyclopentadienyl titanium dichloride, (bis(2-methyl-propyl)phosphino)ethyl-tetramethylcyclopentadienyl titanium dichloride, (diphenylphosphino)ethyl-tetramethylcyclopentadienyl titanium dichloride, (diphenylphosphino)methyldimethylsilyl-tetramethylcyclopentadienyl titanium dichloride. Other examples are the catalysts cited in the list directly above wherein Ln wherein the chloride can be replaced with bromide, hydride, methyl, benzyl, phenyl, allyl, (2-N,N-dimethylaminomethyl)phenyl, (2-N,N-dimethylamino)benzyl, 2,6-dimethoxyphenyl, pentafluorophenyl, and/or wherein the metal is trivalent titanium or trivalent chromium.

In a preferred embodiment, the catalyst precursor is: [2-(2,4,6-iPr3-C6H2)-6-(2,4,6-iPr3-C6H2)-C5H3N]Ti(CH2Ph)3 or [Et2NC(N-2,6-iPr2-C6H3)2]TiCl3

Other non-limiting examples of metal catalyst precursors according to the present invention are: {N′,N″-bis[2,6-di(1-methylethyl)phenyl]-N,N-diethylguanidinato} titanium trichloride, {N′,N″bis[2,6-di(1-methylethyl)phenyl]-N-methyl-N-cyclohexylguanidinato} titanium trichloride, {N′,N″-bis[2,6-di(1-methylethyl)phenyl]-N,N-pentamethyleneguanidinato} titanium trichloride, {N′,N″-bis[2,6-di(methyl)phenyl]-sec-butyl-aminidinato} titanium trichloride, {N-trimethylsilyl,N′-(N″,N″-dimethylaminomethyl)benzamidinato} titanium dichloride THF complex, {N-trimethylsilyl, N′-(N″,N″-dimethylaminomethyl)benzamidinato} vanadium dichloride THF complex, {N,N′-bis(trimethylsilyl)benzamidinato} titanium dichloride THF complex, {N,N′-bis(trimethylsilyl)benzamidinato} vanadium dichloride THF complex.

In a preferred embodiment, the catalyst precursor can be for example: [C5H3N{CMe═N(2,6-iPr2C6H3)}2]FeCl2, [2,4-(t-Bu)2,-6-(CH═NC6F5)C6H2O]2TiCl2 or bis[2-(1,1-dimethylethyl)-6-[(pentafluorophenylimino)methyl] phenolato] titanium dichloride. Other non-limiting examples of metal catalyst precursors according to the present invention can be for example: bis[2-[(2-pyridinylimino)methyl]phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-6-[(phenylimino)methyl]phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-6-[(1-naphthalenylimino)methyl]phenolato] titanium dichloride, bis[3-[(phenylimino)methyl][1,1′-biphenyl]-2-phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-4-methoxy-6-[(phenylimino)methyl]phenolato] titanium dichloride, bis[2,4-bis(1-methyl-1-phenylethyl)-6-[(phenylimino)methyl]phenolato] titanium dichloride, bis[2,4-bis(1,1-dimethylpropyl)-6-[(phenylimino)methyl]phenolato] titanium dichloride, bis[3-(1,1-dimethylethyl)-5-[(phenylimino)methyl][1,1′-biphenyl]-4-phenolato] titanium dichloride, bis[2-[(cyclohexylimino)methyl]-6-(1,1-dimethylethyl)phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-6-[[[2-(1-methylethyl)phenyl]imino]methyl]phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-6-[(pentafluorophenylimino)ethyl]phenolato] titanium dichloride, bis[2-(1,1-dimethylethyl)-6-[(pentafluorophenylimino)propyl]phenolato] titanium dichloride, bis[2,4-bis(1,1-dimethylethyl)-6-[1-(phenylimino)ethyl]phenolato] titanium dichloride, bis[2,4-bis(1,1-dimethylethyl)-6-[1-(phenylimino)propyl]phenolato] titanium dichloride, bis[2,4-bis(1,1-dimethylethyl)-6-[phenyl(phenylimino)methyl]phenolato] titanium dichloride. Other examples are the metal catalyst precursor cited in the list directly above wherein the dichloride can be replaced with dimethyl, dibenzyl, diphenyl, 1,4-diphenyl-2-butene-1,4-diyl, 1,4-dimethyl-2-butene-1,4-diyl or 2,3-dimethyl-2-butene-1,4-diyl; and/or wherein the metal may be zirconium or hafnium.

In a preferred embodiment, the catalyst precursor can be: [2-[[[2-[[[3,5-bis(1,1-dimethylethyl)-2-(hydroxy-κO)phenyl]methyl]amino-κN]ethyl]methylamino-κN]methyl]-4,6-bis(1,1-dimethylethyl)phenolato(2-)-κO] titanium bis(phenylmethyl), [2,4-dichloro-6-[[[2-[[[3,5-dichloro-2-(hydroxy-κO)phenyl]methyl]amino-κN]ethyl]methylamino-κN]methyl]phenolato(2-)-κO] titanium bis(phenylmethyl), [2-[[[[1-[[2-(hydroxy-κO)-3,5-diiodophenyl]methyl]-2-pyrrolidinyl-κN]methyl]amino-κN]methyl]-4-methyl-6-tricyclo[3.3.1.13,7]dec-1-ylphenolato(2-)-κO] titanium bis(phenylmethyl), [2-[[[2-[[[[2-(hydroxy-κO)-3,5-bis(1-methyl-1-phenylethyl)phenyl]methyl]methylamino-κN]methyl]phenyl]methylamino-κN]methyl]-4,6-bis(1-methyl-1-phenylethyl)phenolato(2-)-κO] titanium bis(phenylmethyl), [2,4-dichloro-6-[[[2-[[[[3,5-dichloro-2-(hydroxy-κO)phenyl]methyl]amino-κN]methyl]phenyl]amino-κN]methyl]phenolato(2-)-κO] titanium bis(phenylmethyl). Other examples are the metal catalyst precursor cited in the list directly above wherein bis(phenylmethyl) can be replaced with dichloride, dimethyl, diphenyl, 1,4-diphenyl-2-butene-1,4-diyl, 1,4-dimethyl-2-butene-1,4-diyl or 2,3-dimethyl-2-butene-1,4-diyl; and/or wherein the metal may be zirconium or hafnium.

A non-limiting list of examples of chromium catalysts that would be suitable for use in to the present invention are:

(N-t-butylamido)(dimethyl)(tetramethylcyclopentadienyl)silane chromium bis(trimethylsilyl)methyl, (N-phenylamido)(dimethyl)(tetramethylcyclopentadienyl) silane chromium bis(trimethyl)methyl, (N-sec-butylamido)(dimethyl) (tetramethylcyclopentadienyl)silane chromium bis(trimethylsilyl)methyl, (N-sec-dodecylamido)(dimethyl)(fluorenyl)silane chromium hydride triphenylphosphine, (P-t-butylphospho)(dimethyl)(tetramethylcyclopentadienyl) silane chromium bis(trimethylsilyl)methyl. Other examples are the catalysts cited in the list directly above wherein L1 is hydride, methyl, benzyl, phenyl, allyl, (2-N,N-dimethylaminomethyl)phenyl, (2-N,N-dimethylamino)benzyl; in other words chromium methyl, chromium benzyl, chromium allyl, chromium (2-N,N-dimethylamino)benzyl; and/or wherein the metal is trivalent yttrium or samarium; Other examples are metal catalyst precursors as cited in the list directly above wherein Ln is chloride, bromide, hydride, methyl, benzyl, phenyl, allyl, (2-N,N-dimethylaminomethyl)phenyl, (2-N,N-dimethylamino)benzyl and/or wherein the metal is trivalent titanium or trivalent chromium.

Non-limiting examples of metal catalyst precursors according to the present invention are: N,N′-1,2-acenaphthylenediylidenebis(2,6-bis(1-methylethyl)benzenamine) nickel dibromide, N,N′-1,2-ethanediylidenebis(2,6-dimethylbenzenamine) nickel dibromide, N,N′-1,2-ethanediylidenebis(2,6-bis(1-methyl-ethyl)benzenamine) nickel dibromide, N,N′-1,2-acenaphthylenediylidenebis(2,6-dimethylbenzenamine) nickel dibromide, N,N′-1,2-acenaphthylenediylidenebis(2,6-bis(1-methylethyl)benzenamine) nickel dibromide, N,N′-1,2-acenaphthylenediylidenebis(1,1′-biphenyl)-2-amine nickel dibromide. Other examples are the catalysts cited in the list directly above wherein bromide can be replaced with chloride, hydride, methyl, benzyl and/or the metal can be palladium.

Further non-limiting examples of metal catalyst precursors according to the present invention are: [2-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl]-6-(1,1-dimethylethyl)phenolato-κO] nickel phenyl(triphenylphosphine), [2-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl]-6-(1,1-dimethylethyl)phenolato-κO] nickel phenyl(triphenylphosphine), [2-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl]phenolato-κO] nickel phenyl(triphenylphosphine)-, [3-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl][1,1′-biphenyl]-2-olato-κO] nickel phenyl(triphenylphosphine)-, [2-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl]-4-methoxyphenolato-κO] nickel phenyl(triphenylphosphine), [2-[[[2,6-bis(1-methylethyl)phenyl]imino-κN]methyl]-4-nitrophenolato-κO] nickel phenyl(triphenylphosphine), [2,4-diiodo-6-[[[3,3″,5,5″-tetrakis(trifluoromethyl)[1,1′:3′,1″-terphenyl]-2′-yl]imino-κN]methyl]phenolato-κO] nickel methyl[[3,3′,3″-(phosphinidyne-κP)tris[benzenesulfonato]]] trisodium; [2,4-diiodo-6-[[[3,3″,5,5″-tetrakis(trifluoromethyl)[1,1′:3′,1″-terphenyI]-2′-yl]imino-κN]methyl]phenolato-κO] nickel methyl[[3,3′-(phenylphosphinidene-κP)bis[benzenesulfonato]]]-disodium.

Co-Catalysts Suitable For Step A)

A co-catalyst is optional when a metal catalyst is used. However, a co-catalyst is required when a metal catalyst precursor is used. The function of this co-catalyst is to activate the metal catalyst precursor.

Co-catalysts may be aluminoxanes or a compound selected from the group consisting of fluorinated aryl borane or fluorinated aryl borate (viz. B(R′)_(y) wherein R′ is a fluorinated aryl and y is 3 or 4, respectively). Examples of a fluorinated borane is B(C₆F₅)₃ and of fluorinated borates are [X]⁺[B(C₆F₅)₄]⁻ (e.g. X=Ph₃C, C₆H₅N(H)Me₂).

For example, the co-catalyst can be an organometallic compound. The metal of the organometallic compound can be selected from Group 1, 2, 12 or 13 of the IUPAC Periodic Table of Elements. Preferably, the co-catalyst is an organoaluminum compound, more preferably an aluminoxane, said aluminoxane being generated by the reaction of a trialkyl aluminum compound with water to partially hydrolyze said aluminoxane. For example, trimethyl aluminum can react with water (partial hydrolysis) to form MAO. MAO has the general Formula (Al(CH₃)3_(3−n)O_(0.5n))_(x)·(AlMe₃)_(y) having an aluminum oxide framework with methyl groups on the aluminum atoms.

MAO generally contains significant quantities of free trimethyl aluminum (TMA), which can be removed by drying the MAO to afford the so-called depleted MAO or DMAO. Supported MAO (SMAO) may also be used and may be generated by the treatment of an inorganic support material, typically silica, by MAO.

Alternatively to drying the MAO, when it is desired to remove the free trimethyl aluminum, butylhydroxytoluene (BHT, 2,6-di-t-butyl-4-methylphenol) can be added which reacts with the free trimethyl aluminum.

Neutral Lewis acid modified polymeric or oligomeric aluminoxanes may also be used, such as alkylaluminoxanes modified by addition of a C1-30 hydrocarbyl substituted Group 13 compound, especially a tri(hydrocarbyl) aluminum- or tri(hydrocarbyl) boron compounds, or a halogenated (including perhalogenated) derivatives thereof, having 1 to 10 carbons in each hydrocarbyl or halogenated hydrocarbyl group, more especially a trialkyl aluminum compound.

Other examples of polymeric or oligomeric aluminoxanes are tri(i-butyl) aluminum- or trioctyl aluminum-modified methylaluminoxanes, generally referred to as modified methylaluminoxanes, or MMAO. In the present invention, MAO, DMAO, SMAO and MMAO may all be used as co-catalyst.

In addition, for certain embodiments, the metal catalyst precursors may also be rendered catalytically active by a combination of an alkylating agent and a cation forming agent which together form the co-catalyst, or only a cation forming agent in the case the metal catalyst precursor is already alkylated, as exemplified in T. J. Marks et al., Chem. Rev. 2000, (100), 1391. Suitable alkylating agents are trialkyl aluminum compounds, preferably TIBA. Suitable cation forming agents for use herein include (i) neutral Lewis acids, such as C1-30 hydrocarbyl substituted Group 13 compounds, preferably tri(hydrocarbyl)boron compounds and halogenated (including perhalogenated) derivatives thereof, having from 1 to 10 carbons in each hydrocarbyl or halogenated hydrocarbyl group, more preferably perfluorinated tri(aryl)boron compounds, and most preferably tris(pentafluoro-phenyl) borane, (ii) non polymeric, compatible, non-coordinating, ion forming compounds of the type [C]⁺[A]⁻ where “C” is a cationic group such as ammonium, phosphonium, oxonium, carbonium, silylium or sulfonium groups.

Non-limiting examples of the anionic [“A”] are borate compounds such as C1-30 hydrocarbyl substituted borate compounds, preferably tetra(hydrocarbyl)boron compounds and halogenated (including perhalogenated) derivatives thereof, having from 1 to 10 carbons in each hydrocarbyl or halogenated hydrocarbyl group, more preferably perfluorinated tetra(aryl)boron compounds, and most preferably tetrakis(pentafluoro-phenyl) borate.

Typical examples of [C]⁺[A]⁻ compounds are tri-substituted (alkyl) ammonium salts such as trimethylammonium tetraphenylborate, triethylammonium tetraphenylborate, tripropylammonium tetraphenylborate, tri(n-butyl)ammonium tetraphenylborate, N,N-dimethylanilinium tetraphenylborate, N,N-diethylanilinium tetraphenylborate, N,N-dimethyl-2,4,6-trimethylanilinium tetraphenylborate, trimethylammonium tetrakis(pentafluorophenyl)borate, triethylammonium tetrakis(pentafluorophenyl)-borate, tripropylammonium tetrakis(pentafluorophenyl)borate, tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)-borate, N,N-diethylanilinium tetrakis(pentafluorophenyl)borate, N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(pentafluorophenyl)borate, dioctadecylmethylammonium tetrakis(pentafluorophenyl)borate, trimethylammonium tetrakis(3,5-bis(trifluoro-methyl)phenyl)borate, triethylammonium tetrakis(3,5-bis(trifluoromethyl)phenyl)-borate, tripropylammonium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, tri(n-butyl)ammonium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-diethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, dioctadecylmethylammonium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dimethylanilinium n-butyltris(pentafluorophenyl)borate, N,N-dimethylanilinium benzyltris(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(4-(t-butyldimethylsilyl)-2,3,5,6-tetrafluorophenyl)-borate, N,N-dimethylanilinium tetrakis(4-(tri(i-propyl)silyl)-2,3,5,6-tetrafluoro-phenyl)borate, N,N-dimethylanilinium tris(pentafluorophenyl)(pentafluorophenoxy)borate, N,N-diethylanilinium tris(pentafluorophenyl)(pentafluorophenoxy)borate, N,N-dimethylanilinium tris(pentafluorophenyl)(p-hydroxyphenyl)borate, N,N-diethylanilinium tris(pentafluorophenyl)(p-hydroxyphenyl)borate, trimethylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, triethylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, tripropylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, tri(n-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, dimethyl(t-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, N,N-dimethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl) borate, N,N-diethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl)borate and N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(2,3,4,6-tetrafluorophenyl)borate; dialkyl ammonium salts such as: di(i-propyl)ammonium tetrakis(pentafluorophenyl)borate, and dicyclohexylammonium tetrakis(pentafluorophenyl)borate; trityl (triphenyl methyl) salts such as: trityl tetrakis(pentafluorophenyl)borate, trityl tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, trityl n-butyltris(pentafluorophenyl)borate, benzyltris(pentafluorophenyl)borate, trityl tetrakis(4-(t-butyldimethylsilyl)-2,3,5,6-tetrafluorophenyl)borate, trityl tetrakis(4-(tri(i-propyl)silyl)-2,3,5,6-tetrafluorophenyl)borate, trityl tris(pentafluorophenyl)(pentafluorophenoxy)borate and N,N-dimethylanilinium tris(pentafluorophenyl)(p-hydroxyphenyl)borate; tri-substituted phosphonium salts such as: triphenylphosphonium tetrakis(pentafluorophenyl)borate, tri(o-tolyl)phosphonium tetrakis(pentafluorophenyl)borate, and tri(2,6-dimethylphenyl) phosphonium tetrakis(pentafluorophenyl)borate; di-substituted oxonium salts such as: diphenyloxonium tetrakis(pentafluorophenyl)borate, di(o-tolyl)oxonium tetrakis(pentafluorophenyl)borate, and di(2,6-dimethylphenyl) oxonium tetrakis(pentafluorophenyl)borate; di-substituted sulfonium salts such as: diphenylsulfonium tetrakis(pentafluorophenyl)borate, di(o-tolyl)sulfonium tetrakis(pentafluorophenyl)borate, and bis(2,6-dimethylphenyl)sulfonium tetrakis(pentafluorophenyl)borate.

A supported catalyst may also be used, for example using SMAO as the co-catalyst or other supports for the catalyst. The support material can be an inorganic material. Suitable supports include solid and particulated high surface area, metal oxides, metalloid oxides, or mixtures thereof. Non-limiting examples include: talc, silica, alumina, magnesia, titania, zirconia, tin oxide, aluminosilicates, borosilicates, clays, and mixtures thereof.

Preparation of a supported catalyst can be carried out using methods known in the art, for example i) a metal catalyst precursor can be reacted with supported MAO to produce a supported catalyst; ii) MAO can be reacted with a metal catalyst precursor and the resultant mixture can be added to silica to form the supported catalyst; iii) a metal catalyst precursor immobilized on a support can be reacted with soluble MAO.

Polymerization of the Olefin

Step A) is preferably carried out in an inert atmosphere.

Polymerization of the olefin can for example be carried out in the gas phase below the melting point of the polymer. Polymerization can also be carried out in the slurry phase below the melting point of the polymer. Moreover, polymerization can be carried out in solution at temperatures above the melting point of the polymer product.

It is known to continuously polymerize one or more olefins, such as ethylene or propylene, in solution or in slurry, e.g. in a continuous (multi) CSTR or (multi) loop reactor, in the gas-phase in a reactor with a fluidized or mechanically stirred bed or in a combination of these different reactors, in the presence of a catalyst based on a compound of a transition metal belonging to Groups 3 to 10 of the Periodic Table of the Elements.

For the gas phase process, the polymer particles are kept in the fluidized and/or stirred state in a gaseous reaction mixture containing the olefin(s). The catalyst is introduced continuously or intermittently into the reactor while the polymer constituting the fluidized or mechanically stirred bed is withdrawn from the reactor, also continuously or intermittently. The heat of the polymerization reaction is essentially removed by the gaseous reaction mixture, which passes through heat transfer means before being recycled into the reactor. In addition, a liquid stream may be introduced into the gas-phase reactor to enhance heat removal.

Slurry phase polymerization of olefins is very well known, wherein an olefin monomer and optionally olefin comonomer are polymerized in the presence of a catalyst in a diluent in which the solid polymer product is suspended and transported. Two or more reactors are typically used in such polymerizations when it is desired to produce a multimodal product, in which a polymer made in a first reactor is transferred to a second reactor, where a second polymer having different properties to the first polymer is made in the presence of the first. However it may also be desirable to connect two reactors making monomodal polymers in order to create a swing monomodal/multimodal plant or to increase the flexibility of two small reactors that individually may lack the scale to be economically viable. A slurry reactor may also be combined with a gas phase reactor.

Slurry phase polymerizations are typically carried out at temperatures in the range 50-125° C. and at pressures in the range 1-40 bar. The catalyst used can be any catalyst typically used for olefin polymerization such as those according to the present invention. The product slurry, comprising polymer and diluent and in most cases also components of the catalyst system, olefin monomer and comonomer can be discharged from each reactor intermittently or continuously, optionally using concentrating devices such as hydrocyclones or settling legs to minimize the quantity of fluids withdrawn with the polymer.

The present invention may also be carried out in a solution polymerization process. Typically, in the solution process, the monomer and polymer are dissolved in an inert solvent.

Solution polymerization has some advantages over slurry processes. The molecular weight distribution and the process variables are more easily controlled because the polymerization occurs in a homogeneous phase using homogeneous single-site catalysts (viz. metal catalysts or metal catalyst precursors consisting of solely one type of catalytically active site). The high polymerization temperature typically above 150° C. also leads to high reaction rates. The solution process is used primarily for the production of relatively low molecular weight and/or low density resins which are difficult to manufacture by the liquid slurry or gas phase processes. The solution process is very well suited to produce low density products but it is thought much less satisfactory for higher molecular weight resins because of the excessive viscosity in the reactor as discussed by Choi and Ray, JMS Review Macromolecular Chemical Physics C25(I), 1-55, pg. 10 (1985).

Unlike in the gas phase or slurry process, in a solution process there is usually no polymer solid or powder formed. Typically, the reaction temperature and the reaction pressure are higher than in gas phase or slurry process to maintain the polymer in solution. The solution process tends to use an inert solvent that dissolves the polymer as it is formed, subsequently the solvent is separated and the polymer is pelletized. The solution process is considered versatile in that a wide spectrum of product properties can be obtained by varying the composition of the catalyst system, the pressure, the temperature and the comonomer employed.

Since relatively small reactors are used for a solution process, the, residence time is short and grade changeover can be rapid. For example two reactors in series operated at pressures of up to 50 bar and temperatures up to 250° C. in the reactor can be used. Fresh and recycled olefin monomer is compressed up to 55 bar and pumped into the polymerization reactor by a feed pump. The reaction is adiabatic and maintained at a maximum reactor outlet of about 250° C. Although a single reactor can be used, multiple reactors provide a narrower residence time distribution and therefore a better control of molecular weight distribution.

Another advantage of the present invention is that β-H transfer or elimination during step A) of olefin polymerization process is effectively blocked due to the use of a chain transfer reaction. Beta-hydride (or β-H) elimination is a reaction in which a polymeryl group containing β-hydrogens bonded to a metal center is converted into the corresponding macromolecular alkene and the corresponding metal-bonded hydride. Beta-hydride (or β-H) transfer to monomer is a reaction in which a polymeryl group containing β-hydrogens bonded to a metal center is converted into a macromolecular alkene and the hydride is transferred to an olefin coordinated to the metal thus forming another alkyl group bonded to said metal center. Alternatively, β-alkyl transfer or elimination is also know. In this case, the polymeryl must have an alkyl group (typically a methyl) on the β-carbon. β-Alkyl transfer or elimination typically results in unsaturated macromolecules, containing an allyl chain end, and a new metal alkyl. These are undesired processes since they lead to non-end-functionalized polyolefins.

Step B) Oxidation

The second step of the process according to the present invention, being step B), relates to oxidation of the product obtained in step A) using an oxidizing agent. The main group metal-functionalized first polyolefin blocks are oxidized in step B) to main group metal-functionalized oxidized first polyolefin blocks. The process according to the present invention does thereby preferably not comprise a metal substitution step or sub-step, like for example a hydrolysis or quenching step, especially for example in step B).

As oxidizing agent in step B) the following non-limiting examples may be used: O₂, CO, O₃, CO₂, CS₂, COS, R²NCO, R²NCS, R²NCNR³, CH₂═C(R²)C(═O)OR³, CH₂═C(R²)(C═O)N(R³)R⁴, CH₂═C(R²)P(═O)(OR³)OR⁴, N₂O, R²CN, R²NC, epoxide, aziridine, cyclic anhydride, R³R⁴C═NR², R²C(═O)R³, and SO₃ or a combination of NH₃ and NaCIO or a combination of H₂O₂ and NaOH.

Preferably, the oxidizing agent is selected from oxygen (O₂), ozone (O₃), nitrous oxide (N₂O), epoxide, aziridine, CH₂═C(R²)C(═O)OR³ ((meth)acrylate), CH₂═C(R²)C(═O)N(R³)R⁴ (acryl amide), CH₂═C(R²)P(═O)(OR³)OR⁴ (acrylic or vinylic phosphonate), aldehyde (R²C(═O)R³), ketone (R²C(═O)R³) and imine (R³R⁴C═NR²). These oxidizing agents provide either a metal-alkoxide or metal-amide functionalized polyolefin which can be used directly in step C). The remainder of the oxidizing agents leads to different metal-containing functionalized polyolefins and for these an additional step, e.g. a reaction with epoxide or aziridine, is required to obtain the metal-alkoxide or metal-amide functionalized polyolefin.

Said oxidizing agent may be according to Formula (I) explained below. Said oxidizing agent may be selected from the group consisting of all oxidizing agents specified in Table 1.

As oxidizing agent a compound according to the Formula (I): XY_(a)Z¹ _(b)Z² _(c) may be used, wherein a, b, and c may be 0 or 1. FIG. 1 shows the structure of corresponding oxidizing agents. Table 1 shows an overview of possible oxidizing agents according to the present invention and several embodiments disclosed in that Table are discussed below.

In an embodiment, when a is 1 and b and c are 0 in the XY_(a)Z¹ _(b)Z² _(c) oxidizing agent, the oxidizing agent is XY wherein Y is bonded via a double (Formula I-A) or triple bond (Formula I-B) to X. Examples of this type of oxidizing agents are O₂, and CO and R²NC.

In an embodiment, when a and b are 1 and c is zero in the XY_(a)Z¹ _(b)Z² _(c) oxidizing agent, the oxidizing agent is XYZ¹ wherein either Y and Z¹ are both bonded to X via a double bond (Formula I-C), or wherein Y is bonded to X via a single bond and Z¹ is bonded to X by a triple bond (Formula I-D), or wherein X and Y and Z¹ form a cyclic structure by means of single bonds between X and Y and Z (Formula I-E). Examples of these oxidizing agents are CS₂, COS, R²NCO, R²NCNR³, R²NCS, CH₂═C(R²)C(═O)OR³, CH₂═C(R²)(C═O)N(R³)R⁴, CH₂═C(R²)P(═O)(OR³)OR⁴, N₂O, R²CN, epoxide, aziridine, and cyclic anhydride.

In an embodiment, when a, b and c are 1, the oxidizing agent is XYZ¹Z² wherein Y, Z¹ and Z² are each bonded to X via double bonds (Formula I-F) or wherein Y is bonded to X via a double bond and Z¹ and Z² are independently bonded to X via single bonds (Formula I-G). Examples of oxidizing agents are R³R⁴C═NR², R²C(═O)R³, and SO₃.

The oxidizing agent inserts in the main group metal-carbon.

TABLE 1 Overview of oxidizing agents and intermediate products obtained therewith. Main group metal functionalized oxidized first a b c X Y Z¹ Z² Oxidizing agent polyolefin block I-A 1 0 0 O O — — O₂ Pol-O-M I-B 1 0 0 C O — — CO Pol-C(═O)-M I-B 1 0 0 C NR² — — R²NC Pol-C(═NR²)-M I-C 1 1 0 O O O — O₃ Pol-O-M I-C 1 1 0 C O O — CO₂ Pol-C(═O)O-M I-C 1 1 0 C S S — CS₂ Pol-C(═S)S-M I-C 1 1 0 C O S — COS Pol-C(═S)O-M or Pol- C(═O)S-M I-C 1 1 0 C NR² O — R²NCO Pol-C(═O)N(R²)-M or Pol-C(═NR²)O-M I-C 1 1 0 C NR² NR³ — R²NCNR³ Pol-C(═NR³)NR²-M or Pol-C(═NR²)NR³-M I-C 1 1 0 C NR² S — R²NCS Pol-C(═S)N(R²)-M or Pol-C(═NR²)S-M I-C 1 1 0 CH₂ CR² COOR³ — CH₂═C(R²)C(═O)OR³ Pol- CH₂C(R²)═C(OR³)O-M I-C 1 1 0 CH₂ CR² C(═O)NR³R⁴ — CH₂═C(R²)C(═O)NR³R⁴ Pol-CH₂—C(R²)═C(NR³R⁴)O-M I-C 1 1 0 CH₂ CR² P(═O)(OR³)OR⁴ — CH₂═C(R²)P(═O)(OR³)OR⁴ Pol-CH₂—C(R²)═P(OR³)(OR⁴)O-M I-C 1 1 0 N N O — N₂O Pol-O-M I-D 1 1 0 C R² N — R²CN Pol-C(R²)═N-M I-E 1 1 0 C(R²)R³ C(R⁴)^(R) ₅ O — Epoxide Pol- C(R²)R³C(R⁴)R⁵O-M I-E 1 1 0 C(R²)R³ C(R⁴)R₅ NR⁶ — aziridine Pol- C(R²)R³C(R⁴)R⁵NR⁶-M I-E 1 1 0 C═O R² C(═O)O — cyclic anhydride:—C(═O)R²C(═O)O— Pol-C(═O)—R²—C(═O)O-M I-F 1 1 1 C NR² R³ R⁴ R³R⁴C═NR² Pol-C(R³R⁴)—N(R²)-M I-G 1 1 1 S O O O SO3 Pol-S(═O)₂O-M I-F 1 1 1 C O R² R³ R²C(═O)R³ Pol-C(R²)(R³)O-M

The oxidizing agents as specified in Table 1 will be discussed in more detail here.

With respect to O₂, the metal carbon bond is cleaved and O₂ is inserted to form a peroxide. This initially formed peroxide decomposes to the metal alkoxide: M-Pol→M-O—O-Pol→M-O-Pol. With respect to CO, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(═O)-M. With respect to O₃, the metal carbon bond is cleaved and O is inserted to form M-O-Pol. With respect to CO₂, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═O)O-M functionality. With respect to CS₂, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═S)S-M functionality. With respect to COS, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═S)O-M or Pol-C(═O)S-M functionality. With respect to R²NCO, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═NR²)O-M or Pol-C(═O)NR²-M functionality. With respect to R²NCS, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═NR²)S-M or Pol-C(═S)NR²-M functionality. With respect to R²NCNR³, the oxidizing agent inserts in the metal-carbon bond of the M-Pol to yield the corresponding Pol-C(═NR²)NR³-M or Pol-C(═NR³)NR²-M functionality. With respect to CH₂═CR²COOR³, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-CH₂CR²═C(OR³)O-M. With respect to CH₂═C(R²)C(═O)NR³R⁴, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-CH₂—C(R²)═C(NR³R⁴)O-M. With respect to CH₂═C(R²)P(═O)(OR³)OR⁴, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-CH₂—C(R²)═P(OR³)(OR⁴)O-M. With respect to N₂O, the metal carbon bond is cleaved and oxygen is inserted to form an M-O-Pol. With respect to R²CN, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(R²)═N-M. With respect to R²NC, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(═NR²)-M. With respect to epoxide, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(R²)R³C(R⁴)R⁵O-M. With respect to aziridine, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(R²)R³C(R⁴)R⁵NR⁶-M. With respect to cyclic anhydride, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(═O)—R²—C(═O)O-M. With respect to imine, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(R³)(R⁴)—N(R²)-M. With respect to SO₃, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-S(═O)₂O-M. With respect to a ketone or aldehyde, the metal carbon bond is cleaved and the oxidizing agent is inserted to form a Pol-C(R²)(R³)O-M.

R², R³, R⁴, R⁵, R⁶ are each independently selected from the group consisting of H, SiR⁷ ₃, SnR⁷ ₃ or a C1-C16 hydrocarbyl, preferably selected from hydrogen or C1-C16 hydrocarbyl; where each R⁷ is independently selected from hydride, halide or C1-C16 hydrocarbyl.

As cited above when certain oxidizing agents are used an additional step might be required between step B) and C). In case an additional step is required, step B2) might comprise reacting the reaction product of step B) with an epoxide, aziridine, diol or amino-alcohol.

The reaction conditions for the oxidation step B) can be determined by a skilled person based on e.g. the type of polyolefin used and the type of oxidizing agent used. In an embodiment, the oxidation step is carried at a pressure between 1 and 80 bar. In an embodiment, the oxidation step is carried out at a temperature of between 0° C. and 250° C.

In an embodiment, the oxidation step is carried out for a time period of between 0.5 minutes and 150 minutes, more preferably between 1 minutes and 120 minutes, depending on the reaction temperature and the oxidizing agent.

It should be noted that depending on the reaction conditions different oxidizing agents may be preferred.

Using the catalyst system according to the present invention a degree of chain-end-functionalization of at least 30% of the polyolefins can be obtained, preferably at least 40%, or even at least 50%, or at least 60% or at least 70%, more preferably at least 80%, even more preferably at least 90%, most preferably at least 95%.

Preferably, the process does not include the presence of a non-metal functionalized intermediate. This means that the process of the present invention uses a main group metal-functionalized oxidized first polyolefin block as intermediate which is directly used in the subsequent step C) without prior hydrolysis or quenching. Hence the main group metal-functionalized oxidized first polyolefin block obtained is step B) is directly used in step C) without any intermediate steps. In an embodiment, step C) directly follows step B).

In one embodiment of the invention, the product obtained after step B) can be premixed with a catalyst to be used in step C) prior to step C)

Step C) Forming Second Polymer Block

As discussed above the second polymer block is formed during step C). It may for example be grown via ROP or it may be added via nucleophilic substitution.

In case during step C) a polar block is introduced, the polarity of this polar block may be tuned e.g. by adding during step C) a combination of multiple cyclic monomers of different polarity, by tuning of the polarity of the second polymer block during the pre-synthesis by using combinations of monomers before attaching it to the polyolefin block via nucleophilic substitution, by adding during step C) a combination of multiple second polymers of different polarity, or by adding during step C) a combination of cyclic monomers and a second polymer by nucleophilic substitution. The melt temperature and/or glass transition temperature of the resulting second block of the block copolymer may also be tuned while conserving the crystalline properties by selecting suitable monomers for the second block. In other words, both the physical and mechanical properties may be tuned using the present invention. In addition, the hydrolysis and degradation properties of the polar polymer block may be tuned while not affecting the polyolefin block.

In an embodiment, after step B) and prior to step C) an additional step D) is carried out, wherein step D) comprises reacting the first polyolefin block containing at least one oxidized chain end obtained in step B) with a reactive metal to form a reactive-metal containing functionalized first polyolefin block which acts as catalytic initiator to obtain the block copolymer.

In an embodiment, said reactive metal is a metal that is active in ROP, nucleophilic substitution, such as Mg, Ca, Sc, Y, lanthanides, Ti, Zr, Zn, Al, Ga, Bi and Sn. This is a different metal than the main group metal that is added in step A). Non-limiting examples of reactive-metal containing catalytic initiator groups are: —OM′, —SM′, —NHM′, —NR′″M′, wherein M′ is a reactive metal and wherein R′″ is a hydride or hydrocarbyl.

In case during step C) a polyethylene-like polymer block is introduced, the polymers obtained may be used as compatibilizers for polyolefin-PE blends, in particular iPP-PE blends, wherein PE may for example be LDPE, LLDPE, or HDPE. In case branched second polymer blocks are used, the resulting polymer may be particularly useful for the compatibilization with LDPE and LLDPE.

When it is stated that a second polymer block is formed on the first polyolefin block, the second block is covalently attached to said first block.

In an embodiment, during step C) a diblock copolymer is added to the first block in which case an A-B-C triblock copolymer or a C-B-A-B-C pentablock copolymer is obtained. This can be achieved by pre-synthesizing an A-B diblock copolymer where a block B is added to the polyolefin block (A) using ROP or nucleophilic substitution to form block B followed by ROP to form block C. It is possible that the B blocks are polyethylene-like blocks and the C blocks are polar blocks or that both B and C blocks are polar blocks or that both blocks B and C are different polar blocks. In a specific embodiment, the B block is a polyethylene-like polymer block and the C block is a polar block selected from polyester, polycarbonate, polyamide, and others as specified above.

Step C) is preferably carried out in an inert atmosphere.

An advantage of the present process is that no additional catalyst is needed to carry out the ROP or other carbonylic nucleophilic substitution reaction. The product of step B) is a polyolefin having a main group metal-functionalized oxidized chain end. This chain end can initiate and catalyze ROP, a transesterification reaction or another carbonylic nucleophilic substitution reaction in step C) to provide the block copolymer.

A first polyolefin block containing at least one main group metal-functionalized oxidized chain end obtained in step B) may thus be used to initiate and/or catalyze and/or carry out ROP and/or a transesterification reaction and/or another carbonylic nucleophilic substitution reaction in step C). This may especially for example be possible using an aluminum-alkyl to pacify and/or to obtain the at least one second type of metal-pacified functionalized olefin monomer, so that at least one second type of metal-pacified functionalized olefin monomer bears/comprises an aluminum-alkyl.

Ring-Opening Polymerization Reaction to Grow Second Polymer block.

During step C) of the inventive process the second block may be formed by ROP of cyclic monomers. The main group metal-functionalized chain end (or both) of the first oxidized polyolefin block act(s) as a catalytic initiator where further cyclic monomers can react by opening their ring system and form a longer polymer chain.

The cyclic monomers as preferably used by the present invention are oxygen containing cyclic compounds. The mechanism of ROP is well known to a skilled person and described for example in the Handbook of Ring-Opening Polymerization, 209, Eds. P. Dubois, O. Coulembier, J.-M. Raquez, Wiley VCH, ISBN: 9783527319534.

A mixture of cyclic monomers may also be used to form a random second polymer block to tune the properties. Also the sequential addition of different cyclic monomers may be used.

The main advantage of the present method is that no additional metal catalyst is required to be added since it is in situ formed during step B).

In an embodiment, the cyclic monomer for use in ROP is a polar monomer. The polar cyclic monomer is preferably selected from the group consisting of a lactone, a lactide, a cyclic oligoester (e.g. a di-ester, a tri-ester, a tetra-ester, a penta-ester or higher oligoesters), an epoxide, an aziridine, a combination of epoxide and/or aziridine and CO₂, a cyclic anhydride, a combination of epoxide and/or aziridine and a cyclic anhydride, a combination of epoxide and/or aziridine and CO₂ and a cyclic anhydride, a cyclic N-carboxyanhydride, a cyclic carbonate, a lactam and one or more combinations thereof.

Lactone is used to prepare polylactone blocks; lactide is used to prepare polylactide blocks; cyclic oligoester (e.g. a di-ester, a tri-ester, a tetra-ester or a penta-ester) is used to prepare different types of polyester blocks; epoxide is used to prepare polyether blocks using ROP; a combination of epoxide and CO₂ is used to prepare polycarbonate blocks or poly(carbonate-co-ether) blocks; a combination of epoxide and a cyclic anhydride is used to prepare polyester blocks or poly(ester-co-ether) blocks; a combination of epoxide, cyclic anhydride and CO₂ is used to prepare poly(carbonate-co-ester) blocks or poly(carbonate-co-ester-co-ether) blocks; an N-carboxyanhydride is used to produce polypeptide blocks; a carbonate is used to prepare polycarbonate or polycarbonate-co-ether blocks.

Other cyclic monomers are cyclic sulfur containing compounds such as sulfides; cyclic nitrogen containing compounds such as amines (aziridines), lactams, urethanes, ureas; cyclic phosphorus containing compounds such as phosphates, phosphonates, phosphites, phosphines and phosphazenes; and cyclic silicon containing compounds such as siloxanes, and silyl ethers.

In an embodiment, the at least one cyclic monomer for use in ROP is a monomer selected from the group consisting of cyclic hydrocarbyls containing a reactive functionality that can undergo a nucleophilic substitution reaction at a carbonyl group-containing functionality, such as macrolactones or macrooligolactones, whereby the monomer comprises at least 10 consecutive carbon atoms forming the ring.

In case the cyclic monomer is a cyclic ester, it may be a cyclic ester having a ring size from 4-40 atoms. Preferably the atoms forming the ring, other than the oxygen of the ester functionality or ester functionalities in the case of cyclic oligoesters, are carbon atoms.

A lactone is a cyclic compound having one ester group; a dilactone is a compound having two ester groups; a trilactone is a compound having three ester groups; a tetralactone is a compound having four ester groups; a pentalactone is a compound having five ester groups; an oligolactone is a compound having 2-20 ester groups.

Examples of cyclic esters that can be used as monomer in step C) include β-propiolactone, β-butyrolactone, 3-methyloxetan-2-one, γ-valerolactone, ε-caprolactone, ε-decalactone, 5,5-dimethyl-dihydro-furan-2-one, 1,4-dioxepan-5-one, 1,5-dioxepan-2-one, 3,6-dimethylmorpholine-2,5-dione, 1,4-dioxepan-7-one, 4-methyl-1,4-dioxepan-7-one, (S)-γ-hydroxymethyl-γ-butyrolactone, γ-octanoic lactone, γ-nonanoic lactone, δ-valerolactone, δ-hexalactone, δ-decalactone, δ-undecalactone, δ-dodecalactone, glycolide, lactide (L, D, meso), heptalactone, octalactone, nonalactone, decalactone, 11-undecalactone, 12-dodecalactone, 13-tridecalactone, 14-tetradecalactone, 15-pentadecalactone (or ω-pentadecalactone), globalide, 16-hexadecalactone, ambrettolide, 17-heptadecalactone, 18-octadecalactone, 19-nonadecalactone, ethylene brassylate, butylene brassylate, cyclic butyl terephthalate, cyclic butyl adipate, cyclic butyl succinate, cyclic butyl terephthalate oligomers.

The cyclic esters, in particular where these are lactones, may be in any isomeric form and may further contain organic substituents on the ring that do not prevent the ROP. Examples of such cyclic esters include 4-methyl caprolactone, ε-decalactone, the lactone of ricinoleic acid (a 10-membered ring with a hexyl branched on the (co-1)-position) or the hydrogenated version of thereof, 13-hexyloxacyclotridecan-2-one (a macrocycle with a hexyl branch on the α-position), and the like.

It is further possible that the cyclic ester comprise one or more unsaturations in the ring. Examples of such cyclic esters include 5-tetradecen-14-olide, 11-pentadecen-15-olide, 12-pentadecen-15-olide (also known as globalide), 7-hexadecen-16-olide (also known as ambrettolide) and 9-hexadecen-16-olide.

The cyclic ester may further have one or more heteroatoms in the ring, provided that such do not prevent the ROP. Examples of such cyclic esters include 1,4-dioxepan-5-one, 1,5-dioxepan-2-one, 3,6-dimethylmorpholine-2,5-dione, 1,4-oxazepan-7-one, 4-methyl-1,4-oxazepan-7-one, 10-oxahexadecanolide, 11-oxahexadecanolide, 12-oxahexadecanolide and 12-oxahexadecen-16-olide.

In an embodiment, first a monomer is used to form a second block and subsequently a polar monomer is used to form an additional block on the polyethylene-like block, viz. polyolefin-polyethylen-like-polar or polar-polyethylene-like-polyolefin-polyethylene-like-polar in case of a telechelic polyolefin block. In an embodiment, the polyolefin is isotactic PP, the polyethylene-like polymer is a PAmb or PPDL and the polar polymer is PCL or PLA.

Nucleophilic Substitution to Add Second Polymer Block

During step C) a nucleophilic substitution reaction can be carried out to add a second polymer block to at least one chain end of the first polymer block.

The result of step B) is a functionalized first polymer block having at one or both oxidized chain ends a main group metal. This main group metal functionalized first polyolefin block can be used as catalytic initiator in a nucleophilic substitution reaction.

In the context of the present invention, a nucleophilic substitution reaction describes the reaction of a nucleophilic chain end with a carbonyl group-containing functionality present in a polymer added during step C).

The second polymer block to be added during step C) to afford the block copolymer comprises at least one carbonyl-group containing functionality may for example be selected from the group consisting of a polyester, a polycarbonate, a polyamide, a polyurethane, a polyurea, a random or block poly(carbonate-ester), poly(carbonate-ether), poly(ester-ether), poly(carbonate-ether-ester), poly(ester-amide), poly(ester-ether-amide), poly(carbonate-amide), poly(carbonate-ether-amide), poly(ester-urethane), poly(ester-ether-urethane), poly(carbonate-urethane), poly(carbonate-ether-urethane), poly(ester-urea), poly(ester-ether-urea), poly(carbonate-urea), poly(carbonate-ether-urea), poly(ether-amide), poly(amide-urethane), poly(amide-urea), poly(urethane-urea) or one or more combination thereof.

In an embodiment, besides a second polymer block also cyclic monomers are added to provide a combination of ROP and nucleophilic substitution reactions to yield the final “polyolefin-b-polar polymer” or “polyolefin-b-polyethylene-like polymer” or “polyolefin-b-nonpolar polymer”. This approach provides a versatile method to tune the physical and mechanical properties of the second polymer block of the block copolymer.

In an embodiment, a co-catalyst is present during step C) in case of nucleophilic substitution reaction. More preferably, when using a Cr- or Co-based catalyst and using epoxide and/or aziridines in combination with CO₂ or using epoxide and/or aziridines in combination with cyclic anhydride or using epoxide and/or aziridines in combination with CO₂ and cyclic anhydrides. Examples of a co-catalyst suitable for use are N-methyl-imidazole, 4-dimethylanimopyridine, bis(triphenyl-phosphoranylidene)ammonium chloride) bis(triphenyl-phosphoranylidene)ammonium azide), tricyclehexylphosphine, triphenylphosphine, tris(2,4,6-trimethoxyphenyl)phosphine and 1,5,7-triazabicyclododecene.

For the ROP or nucleophilic substitution reaction a catalyst is used. Specific examples of catalysts include among others mineral acids, organic acids, organic bases, metallic compounds such as hydrocarbyls, oxides, chlorides, carboxylates, alkoxides, aryloxides, amides, salen complexes, β-ketiminato complexes, guanidinato complexes of tin, titanium, zirconium, aluminum, bismuth, antimony, magnesium, calcium and zinc and lipase enzymes. Examples of suitable catalysts are as reported by J. Otera and J. Nishikido, Esterification, p. 52-99, Wiley 2010; J. Otera Chem. Rev. 1993, 93, 1449; H. Kricheldorf Chem. Rev. 2009, 109, 5579; D.-W. Lee, Y.-M. Park, K.-Y. Lee Catal. Surv. Asia 2009, 13, 63; A. B. Ferreira, A. L. Cardoso, M. J. da Silva International Schilarity research Network, 2012, doi: 10.5402/2012/142857; Z. Helwani, M. R. Othman, \N. Aziz, J. Kim, W. J. N. Fernando Appl. Catal. A: Gen. 2009, 363, 1; N. E. Kamber, W. Jeong, R. M. Waymouth, R. C. Pratt, B. G. G. Lohmeijer, J. L. Hedrick, Chem. Rev., 2007, 107, 5813; D. Bourissou, S. Moebs-Sanchez, B. Martin-Vaca, C. R. Chimie, 2007, 10, 775.

Examples of organic acid as catalysts for ROP or nucleophilic substitution according to the present invention are the following, an acid selected from the group comprising diethylether complex of hydrogen chloride, fluorosulfonic acid, trifluoromethanesulfonic acid, methyl trifluorosulfonate, ethyl trifluoromethane-sulfonate n-propyl trifluorosulfonate, and i-propyl trifluorosulfonate)), metal (yttrium, aluminum, bismuth) triflates, the acidic catalyst may also be selected from a group of compounds that are formed by combining a strong Lewis acid and a strong Brønsted acid. A specific example of such a compound is an equimolar combination of fluorosulfonic acid and antimony pentafluoride.

Examples of organic bases as catalysts for ROP or nucleophilic substitution according to the present invention are the following. The bases herein are defined as super bases and are referred as compounds which exhibit basicity significantly higher than that of commonly used amines such as pyridine or triethylamine. Super bases can broadly be divided into three categories: organic, organometallic and inorganic. Organic super bases comprise molecules characterized as amidines, guanidines, multicyclic polyamines and phosphazenes.

Amidines are classified as amine compounds which have an imine function adjacent to the α-carbon:

Structurally these correspond to amine equivalents of carboxylic esters. The alkyl substituents R⁵¹-R⁵⁴ are independently selected from hydrogen and C1-C16 alkyl substituents that may be linear, branched, cyclic or aromatic. Further these alkyl substituents R⁵¹-R⁵⁴ may be unsaturated, halogenated or carry a specific functionality such as hydroxyl, ether, amine, cyano, or nitro functions. The alkyl substituents R⁵¹-R⁵⁴ may also form bicyclic structures, where an increased ring strain may lead to stronger basicity. Examples of cyclic amidines are 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 3,3,6,9,9-pentamethyl-2,10-diazabicyclo-[4.4.0]dec-1-ene, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). DBU is considered to be the strongest amidine derivative.

Guanidines can similarly be classified as amines which possess two imine functions adjacent to the α-carbon:

These correspond to amine equivalents of ortho esters and show the strongest Brønsted basicity among amine derivatives. The basicity of guanidine is close to that of a hydroxyl-ion, which is the strongest base in aqueous chemistry. The alkyl substituents R⁵⁵-R⁵⁹ are independently selected from hydrogen and C1-C16 alkyl substituents that may be linear, branched, cyclic or aromatic. Further these alkyl substituents R⁵⁵-R⁵⁹ may be unsaturated, halogenated or carry a specific functionality such as hydroxyl, ether, amine, cyano, or nitro functions. The alkyl substituents R⁵⁵-R⁵⁹ may also form bicyclic structures, where an increased ring strain may lead to stronger basicity. Examples of common guanidines are 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), N-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), N,N,N′,N′-tetramethyl-guanidine (TMG), or N,N,N′,N′,N″-pentamethylguanidine (PMG) can be given as examples of guanidine compounds.

Phosphazenes are organic super bases containing a pentavalent phosphorus atom bonded to four nitrogen functions of three amine substituents and one imine substituent.

Phosphazenes are classified as P_(n) bases, where n denotes the number of phosphorus atoms in the molecule. The basicity of phosphazenes increase with an increasing amount of phosphorous atoms in the molecule. A P₄ base is considered to have a basicity parallel to organo lithium compounds. The alkyl substituents R⁶⁰-R⁶¹ are independently selected from C1-C16 alkyl substituents that may be linear, branched, cyclic or aromatic. Further these alkyl substituent may be unsaturated, halogenated or carry a specific functionality such as hydroxyl, ether, amine, cyano, or nitro functions. The alkyl substituents R may be the same or mixtures of various combinations. Suitable examples of phosphazenes according to the present invention are 1-t-butyl-2,2,4,4,4-pentakis(dimethylamino)-2A⁵,4A⁵- catenadi(phosphazene) (P₂-t-Bu) and 1-t-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)-phosphoranylidenamino]-2A⁵,4A⁵- catenadi(phosphazene) (P₄-t-Bu).

Examples of organometallic or inorganic bases as catalysts for ROP, transesterification or nucleophilic substitution according to the present invention are the following. Organometallic or inorganic super bases consist of metal alkyls, metal alkoxides and metal amides such as butyl lithium, potassium t-butoxide, lithium diisopropylamide and lithium bis(trimethylsilyl)amide to give an example of these. Mixtures of organometallic super bases can also be used to further enhance their reactivity; a mixture of butyl lithium and potassium t-butoxide an example of such. Inorganic super bases are frequently compounds with anions that are small in size and exhibit a high charge density such as metal hydrides in general and lithium nitride to give as examples.

Examples of tin-based catalysts for ROP or nucleophilic substitution according to the present invention are the following. Tetravalent tin compounds which are used as metal catalysts are tin oxide, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin di(2-ethylhexoate), dioctyltin dilaurate, dibutyltin maleate, di(n-octyl)tin maleate, bis(dibutyl acetoxy tin) oxide, bis(dibutyl lauroxyloxy tin) oxide, dibutyltin dibutoxide, dibutyltin dimethoxide, dibutyltin disalicylate, dibutyltin bis(isooctyl maleate), dibutyltin bis(isopropyl maleate), dibutyltin oxide, tributyltin acetate, tributyltin isopropyl succinate, tributyltin linoleate, tributyltin nicotinate, dimethyltin dilaurate, dimethyltin oxide, dioctyltin oxide, bis(tributyltin) oxide, diphenyltin oxide, triphenyltin acetate, tri-propyltin acetate, tri-propyltin laurate, and bis(tri-propyltin) oxide. Suitable tin-containing compounds include the carboxylate salts of divalent tin in which the carboxylate group is derived from a monobasic acid, an aliphatic dibasic acid, a tribasic aliphatic acid, a monobasic aromatic acid, a dibasic aromatic acid or a tribasic aromatic acid as hereinafter described in connection with the process for the production of esters. The carboxylate salt may be added as such or may be formed ‘in situ’ by reacting divalent tin oxide with a carboxylic acid. Divalent tin compounds which are used are tin oxide, tin bis(2-ethyl-hexanonate), tin bis(2,6-tBu-4-Me-C₆H₂O), tin oxalate, tin dichloride.

Examples of titanium-based catalysts for ROP or nucleophilic substitution according to the present invention are the following. Titanium compounds which can be employed include tetramethyl titanate, tetraethyl titanate, tetraallyl titanate, tetrapropyl titanate, tetraisopropyl titanate, tetrabutyl titantate, tetraisobutyl titanate, tetraamyl titanate, tetracyclopentyl titanate, tetrahexyl titanate, tetracyclohexyl titanate, tetrabenzyl titanate, tetraoctyl titanate, tetraethylhexyl titanate, tetranonyl titanate, tetradecyl titanate, and tetraoleyl titanate, tetraphenyl titanate, tetra(o-tolyl) titanate, tetra(m-tolyl) titanate, and tetra(1-napthyl) titante and tetra(2-naphthyl) titanate. Mixed alkyl titanate compounds would include trimethylbutyl titanate, dimethyldibutyl titanate, triethylbutyl titanate, methyl isopropyl dibutyl titanate, diethyl dibutyl titanate, propyl tributyl titanate, ethyl tricyclohexyl titanate, diisopropyl dioctadecyl titanate, and dibutyl dioctadecyl titanate.

Examples of bismuth-based catalysts for ROP or nucleophilic substitution according to the present invention are the following. Bismuth tris(2-ethyl-hexanoate), bismuth trisacetate, bismuth trishexanoate, bismuth tristriflate, bismuth subsalicylate (also called orthosalicylate), bismuth subcarbonate, BiCl₃, BiBr₃, BiI₃, Bi₂O₃, Ph₂BiOEt, Ph₂BiOMe, Ph₂BiOtBu, Ph₂BiOBr, Ph₂BiI, [SCH₂CH₂O]Bi[SCH₂CH₂OH], B(OEt)₃, bismuth aminotriethanolate, bismuth lactate, bismuth nitrate, bismuthyl nitrate, bismuth carbonate, bismuthyl carbonate, bismuthyl hydroxide, bismuth ortho hydroxide (Bi(OH)₃).

Examples of organometallic/metal coordination complexes for use as catalysts for ROP or nucleophilic substitution, especially transerterification, according to the present invention are the following. Besides metal halide, triflate, hydrocarbyl, alkoxide, aryloxide, amide, carboxylate, acetylacetonate complexes or complexes consisting of combinations of these substituents of Li, Na, K, Mg, Ca, Sc, Y, lanthanides, Ti, Zr, Zn, Al, Ga, Bi and Sn, distinct and well-defined organometallic and metal coordination complexes have been applied as metal catalysts for the ROP of various kinds of cyclic esters or cyclic carbonates and for the transesterification of polymers containing carboxylic acid esters or carbonic acid esters. Examples are salen, salan, salalen, guanidinate, porphyrin, β-ketiminate, phenoxy-imine, phenoxy-amine, bisphenolate, trisphenolate, alkoxyamine, alkoxyether and alkoxythioether complexes of Mg, Ca, Sc, Y, lanthanides, Ti, Zr, Zn, Al, Ga, Bi and Sn.

Recently, several well-defined metallic initiators have been developed for the controlled, living ROP of the various isomers of LA, namely rac-, L-, D- and meso-LA, as disclosed for example in O'Keefe et al. (B. J. O'Keefe, M. A. Hillmyer, W. B. Tolman, J. Chem. Soc., Dalton Trans., 2001, 2215-2224), or in Lou et al. (Lou, C. Detrembleur, R. Jérôme, Macromol. Rapid. Commun., 2003, 24, 161-172), or in Nakano et al. (K. Nakano, N. Kosaka, T. Hiyama, K. Nozaki, J. Chem. Soc., Dalton Trans., 2003, 4039-4050), or in Dechy-Cabaret et al. (O. Dechy-Cabaret, B. Martin-Vaca, D. Bourissou, Chem. Rev., 2004, 104, 6147-6176), or in Wu et al. (Wu, T.-L Yu, C.-T. Chen, C.-C. Lin, Coord. Chem. Rev., 2006, 250, 602-626), or in Amgoune et al. (Amgoune, C. M. Thomas, J.-F. Carpentier, Pure Appl. Chem. 2007, 79, 2013-2030). They are based mostly on: non-toxic zinc (M. Cheng, A. B. Attygalle, E. B. Lobkovsky, G. W. Coates, J. Am. Chem. Soc., 1999, 121, 11583-11584; B. M. Chamberlain, M. Cheng, D. R. Moore, T. M. Ovitt, E. B. Lobkovsky, G. W. Coates, J. Am. Chem. Soc., 2001, 123, 3229-3238; C. K. Williams, L. E. Breyfogle, S. K. Choi, W. Nam, V. G. Young Jr., M. A. Hillmyer, W. B. Tolman, J. Am. Chem. Soc., 2003, 125, 11350-11359; G. Labourdette, D. J. Lee, B. O. Patrick, M. B. Ezhova, P. Mehrkhodavandi, Organometallics, 2009, 28, 1309-1319; Z. Zheng, G. Zhao, R. Fablet, M. Bouyahyi, C. M. Thomas, T. Roisnel, O. Casagrande Jr., J.-F. Carpentier, New J. Chem., 2008, 32, 2279-2291), aluminum (N. Spassky, M. Wisniewski, C. Pluta, A. LeBorgne, Macromol. Chem. Phys., 1996, 197, 2627-2637; T. M. Ovitt, G. W. Coates, J. Am. Chem. Soc., 1999, 121, 4072-4073; M. Ovitt, G. W. Coates, J. Am. Chem. Soc., 2002, 124, 1316-1326; N. Nomura, R. Ishii, Y. Yamamoto, T. Kondo, Chem. Eur. J., 2007, 13, 4433-4451; H. Zhu, E. Y.-X. Chen, Organometallics, 2007, 26, 5395-5405), non-toxic bismuth H. Kricheldorf Chem. Rev. 2009, 109, 5579 or Group 3 metals and lanthanides (C.-X. Cai, A. Amgoune, C. W. Lehmann, J.-F. Carpentier, Chem. Commun., 2004, 330-331; A. Amgoune, C. M. Thomas, T. Roisnel, J.-F. Carpentier, Chem. Eur. J., 2006, 12, 169-179; A. Amgoune, C. M. Thomas, S. Ilinca, T. Roisnel, J.-F. Carpentier, Angew. Chem. Int. Ed., 2006, 45, 2782-2784).

The amount of the catalyst used for step C) is selected from a range of for example 0.0001 to 0.5% by weight, preferably 0.001 to 0.1% by weight based on the cyclic ester, or the number of carbonyl group-containing functionalities in the second polymer block added during step C).

In the prior art, usually after preparation of the first polyolefin block, this block is hydrolyzed to an —OH end group. To this —OH end group usually an aluminum center is added using e.g. trimethyl aluminum. This will lead to an Al—O-Pol species that will undergo the ROP or nucleophilic substitution reaction of a second polymer block. Alternatively, a catalyst like tin octanoate is added. However, these extra steps are not required when using the method according to the present invention.

After step C) is finished, the block-copolymer is obtained. In an embodiment, the reaction mixture is quenched using a quenching agent, preferably a protic polar reagent, more preferably an alcohol, preferably methanol or ethanol. However, water can also be used. The product obtained after this quenching is a crude product which may contain also the polyolefin obtained in step A) and/or polymer obtained from the ROP, transesterification or nucleophilic substitution reaction in step C) that is not attached to the first polyolefin block. For most applications, however, the crude product may be used as such without further purification.

If polymer obtained from the ROP or nucleophilic substitution reaction in step C) has to be removed from the product, this crude product may for example be subjected to an additional step of work up. This work up step may comprise a precipitation. For example a precipitation in a solvent, such as THF or other organic solvents, such as chloroform. This can also be called an extraction in case the second block comprises a polar block because any polar polymer formed will be extracted out of the crude product leaving the block copolymer and possibly polyolefin.

A person skilled in the art will be able to determine the required steps in order to purify the block copolymer products, using e.g. one or more precipitation and/or extraction steps using one or more solvents. The product may also be dried prior to use thereof.

Further Embodiments

The present invention relates to a three-step process for the preparation of block copolymers.

Using the process according to the present invention, block copolymers can be obtained. In an embodiment, the block copolymer has an number average molecular weight (M_(n)) for example between 500 and 1,000,000 g/mol, preferably between 1,000 and 200,000 g/mol.

The polyolefins according to the present invention preferably have a polydispersity index (Ð) of between 1.1 and 10.0, more preferably between 1.1 and 5.0, even more preferably between 1.1 and 4.0.

The polyolefin blocks may be linear or branched (both long chain branched and short chain branched), atactic, isotactic or syndiotactic, preferably, isotactic polyolefins in the case of poly-α-olefins, wherein the isotactic polyolefin is preferably isotactic polypropylene.

According to a specific, non-limiting embodiment of the present invention, the polyolefin block may be linear low density polyethylene (LLDPE), high density polyethylene (HDPE), ethylene-propylene copolymer (EP), atactic, isotactic or syndiotactic PP (aPP, iPP, sPP, respectively), poly-4-methyl-1-pentene (P4M1P) or atactic, isotactic or syndiotactic polystyrene (aPS, iPS, sPS, respectively).

The block copolymers according to the present invention may have a mass fraction of polyolefin (mfPol) of between 10% and 90%, preferably between 30% and 70%. The mass fraction mfPol is defined by the mass of the polyolefin divided by the total mass of the block copolymer.

The block copolymers according to the present invention may have a volume fraction of second polymer (vfPol) of between 90% and 10%, preferably between 70% and 30%. The volume fraction vfPol is defined by the volume of the second polymer block(s) divided by the total volume of the block copolymer.

Examples of polymers having a polyolefin first block and a polar polymer second block that can be prepared using the present method are HDPE-b-PCL, HDPE-b-PLA, HDPE-b-PBA, HDPE-b-PBS, HDPE-b-PEB, HDPE-b-poly(CL-co-PDL), HDPE-b-poly(BA-co-EB), HDPE-b-poly(BA-co-PDL), LLDPE-b-PCL, LLDPE-b-PLA, LLDPE-b-PBA, LLDPE-b-PBS, LLDPE-b-PEB, LLDPE-b-poly(BA-co-EB), LLDPE-b-poly(CL-co-PDL), LLDPE-b-poly(BA-co-PDL), EP-b-PCL, EP-b-PLA, EP-b-PBA, EP-b-PBS, EP-b-PEB, EP-b-poly(BA-co-EB), EP-b-poly(CL-co-PDL), EP-b-poly(BA-co-PDL), aPP-b-PCL, iPP-b-PLA, aPP-b-PBA, aPP-b-PBS, aPP-b-PEB, aPP-b-poly(BA-co-EB), aPP-b-poly(CL-co-PDL), aPP-b-poly(BA-co-PDL), iPP-b-PCL, iPP-b-PLA, iPP-b-PBA, iPP-b-PBS, iPP-b-PEB, iPP-b-poly(BA-co-EB), iPP-b-poly(CL-co-PDL), iPP-b-poly(BA-co-PDL), sPP-b-PCL, sPP-b-PLA, sPP-b-PBA, sPP-b-PBS, sPP-b-PEB, sPP-b-poly(BA-co-EB), sPP-b-poly(CL-co-PDL), sPP-b-poly(BA-co-PDL), iP4M1P-b-PCL, iP4M1P-b-PBA, iP4M1P-b-PBS, iP4M1P-b-PEB, iP4M1P-b-poly(BA-co-EB), iP4M1P-b-poly(CL-co-PDL), iP4M1P-b-poly(BA-co-PDL), aPS-b-PCL, aPS-b-PBA, aPS-b-PBS, aPS-b-PEB, aPS-b-poly(BA-co-EB), aPS-b-poly(CL-co-PDL), aPS-b-poly(BA-co-PDL), iPS-b-PCL, iPS-b-PBA, iPS-b-PBS, iPS-b-PEB, iPS-b-poly(BA-co-EB), iPS-b-poly(CL-co-PDL), iPS-b-poly(BA-co-PDL), sPS-b-PCL, sPS-b-PBA, sPS-b-PBS, sPS-b-PEBL, sPS-b-poly(BA-co-EB), sPS-b-poly(CL-co-PDL), sPS-b-poly(BA-co-PDL) and many other polymers.

Examples of polymers having a polyolefin first block and a polyethylene-like polymer second block that can be prepared using the present method are HDPE-b-PPDL, HDPE-b-PAmb, HDPE-b-poly(PDL-co-Amb), LLDPE-b-PPDL, LLDPE-b-PAmb, LLDPE-b-poly(PDL-co-Amb), EP-b-PPDL, EP-b-PAmb, EP-b-poly(PDL-co-Amb), aPP-b-PPDL, aPP-b-PAmb, aPP-b-poly(PDL-co-Amb), iPP-b-PPDL, iPP-b-PAmb, iPP-b-poly(PDL-co-Amb), sPP-b-PPDL, sPP-b-PAmb, sPP-b-poly(PDL-co-Amb), iP4M1P-b-PPDL, iP4M1P-b-PAmb, iP4M1P-b-poly(PDL-co-Amb), aPS-b-PPDL, aPS-b-PAmb, aPS-b-poly(PDL-co-Amb), iPS-b-PPDL, iPS-b-PAmb, iPS-b-poly(PDL-co-Amb), sPS-b-PPDL, sPS-b-PAmb, sPS-b-poly(PDL-co-Amb).

Examples of polymers having a polyolefin first block, a polyethylene-like polymer second block and a polar polymer third block that can be prepared using the present method are HDPE-b-PPDL-b-PCL, HDPE-b-PAmb-b-PCL, HDPE-poly(PDL-co-Amb)-b-PCL, LLDPE-b-PPDL-b-PCL, LLDPE-b-PAmb-b-PCL, LLDPE-poly(PDL-co-Amb)-b-PCL, EP-b-PPDL-b-PCL, EP-b-PAmb-b-PCL, EP-b-poly(PDL-co-Amb)-b-PCL, aPP-b-PPDL-b-PCL, aPP-b-PAmb-b-PCL, aPP-poly(PDL-co-Amb)-b-PCL, iPP-b-PPDL-b-PCL, iPP-b-PAmb-b-PCL, iPP-poly(PDL-co-Amb)-b-PCL, sPP-b-PPDL-b-PCL, sPP-b-PAmb-b-PCL, sPP-poly(PDL-co-Amb)-b-PCL, iP4M1P-b-PPDL-b-PCL, iP4M1P-b-PAMb-b-PCL, iP4M1P-b-poly(PDL-co-Amb)-b-PCL, aPS-b-PPDL-b-PCL, aPS-b-PAmb-b-PCL, aPS-poly(PDL-co-Amb)-b-PCL, iPS-b-PPDL-b-PCL, iPS-b-PAmb-b-PCL, iPS-poly(PDL-co-Amb)-b-PCL, sPS-b-PPDL-b-PCL, sPS-b-PAmb-b-PCL, sPS-poly(PDL-co-Amb)-b-PCL.

The block copolymers prepared according to the present invention may for example be used to introduce polar properties to enhance the interfacial interactions in polyolefins blends with polar polymers or blends with different polyolefins with PEs. They may be used as compatibilizers to improve properties such as adhesion. They may be used to improve barrier properties, especially against oxygen, for polyolefin films. They may be used as compatibilizers to highly polar polymers such as starch, cellulose or EVOH, or for polyolefin-based composites with inorganic fillers such as glass or talc. They may be used in drug delivery devices, nonporous materials/membranes.

In an embodiment, the first polyolefin block is attached to the second polymer block which is a polyester and the polymer obtained is a di-block copolymer (polyolefin-block-polyester). This di-block copolymer can for example be used for packaging applications. In an embodiment, this di-block copolymer is prepared using ROP using a cyclic ester. In an embodiment, the polyolefin is LLDPE.

According to a specific, non-limiting embodiment of the present invention, the polyolefin block may be HDPE, LLDPE, EP, aPP, iPP, sPP, iP4M1P, aPS, iPS or sPS.

In an embodiment, in case the second block is formed by ROP and when the first polyolefin block is HDPE, the second polymer block is not polycaprolactone, polyvalerolactone or polylactic acid. In an embodiment, in case the second block is formed by ROP and when the first polyolefin block is iPP, the second polymer block is not polycaprolactone, polyvalerolactone or polylactic acid.

Advantages of the Present Invention

An advantage of the present invention is the reduction of the number of process steps that are required towards the synthesis of block copolymers. The process according to the present invention cost less time and energy and is less material consuming than the processes according to the prior art.

Another advantage of the present invention is that in principle only one single catalyst is required during the entire process, being the metal catalyst or metal catalyst precursor in step A). The catalyst for step C) is in situ generated upon oxidation of the main group metal-functionalized first polyolefin block.

An advantage of the present invention is that it is possible to produce a wide variety of block copolymers, e.g. diblock A-B or triblock B-A-B or triblock A-B-C or pentablock C-B-A-B-C, depending on the need of the specific application.

The process according to the invention can be a so-called cascade or cascade-like process. Preferably, step B) can thereby be carried out directly after step A) and/or step C) can be carried out directly after step B), preferably for example in a series of connected reactors, preferably continuously. Such a process according to the present invention can thereby be carried out without a metal-substitution step, for example by hydrolysis. A metal-substitution step can thereby for example be any step removing the metal to give a reactive organic function. Preferably, the steps A), B) and C) are carried out in a so-called cascade-like process. In other words, the process can be a single multi-step process using a series of reactors for example without metal-substitution, for example by hydrolysis, without work-up, without drying and/or without purification steps. It should be noted that an extruder is also considered as a reactor in the context of the present invention. It should be noted that an extruder is also considered as a reactor in the context of the present invention.

After chain transfer of the polyolefin to a main group metal hydrocarbyl or a main group metal hydride, in situ oxidation and successive formation of at least one second polymer block either by using a grafting from approach growing a second polymer block by ROP of one or more cyclic monomers or by using a grafting onto approach adding a second polymer block via nucleophilic substitution, the desired block copolymers can be obtained in high yield thereby reducing considerably the number or process steps that are required according to prior art processes, such as metal substitution, intermediate work up, filtration, drying etc. This is an advantage of the present invention.

Examples

The invention is further illustrated by the following non-limiting examples merely used to further explain certain embodiments of the present invention.

All examples relate to step C) of the process according to the present invention, wherein a second polymer block was formed using a previously prepared first polyolefin block having a hydroxyl-functionalized chain end. The preparation of these first polyolefin blocks having a hydroxyl-functionalized chain end is discussed below.

Experimental Section

All manipulations were performed under an inert dry nitrogen atmosphere using either standard Schlenk or glove box techniques. Dry, oxygen free toluene was employed as solvent for all polymerizations. rac-Me₂Si(Ind)₂ZrCl₂ (1) and rac-Me₂Si(Ind)₂HfCl₂ (2) were purchased from MCAT GmbH, Konstanz, Germany. [C₅Me₄CH₂CH₂NMe₂]TiCl₂ (3) was prepared as disclosed in WO9319104. Methylaluminoxane (MAO, 30 wt. % solution in toluene) was purchased from Chemtura. Diethyl zinc (1.0 M solution in hexanes), triisobutyl aluminum (1.0 M solution in hexanes). Tetrachloroethane-d₂ (TCE-d₂) and CL were purchased from Sigma Aldrich.

Typical Polymerization Procedure

For the preparation of polyethylene-block-polycaprolactone copolymers, a multi-steps continuous process carried out in a single reactor was applied. The first step A) consists of ethylene homopolymerization followed by two consecutive steps of in-situ oxidation (step B) and ROP (step C) of CL. Specifically, the polymerization reactions were carried out in stainless steel Büchi reactors (300 mL). Prior to the polymerization, the reactor was dried in vacuum at 40° C. and flushed with nitrogen. Toluene (70 mL) and MAO solution (5 mL of 30% solution in toluene, Al/Zr≈1000) were added and stirred at 50 rpm for 30 min. TIBA (4 mL, 1.0 M solution in hexanes, Al/Zr≈200 equiv.) and DEZ (1.0 mL, 1.0 M solution in hexanes, Al/Zr≈50 equiv.) were added and stirred for 10 min. The solution was saturated with a predefined pressure of ethylene. In a glove box, the metal catalyst precursor was dissolved in toluene (3 mL) and transferred into the reactor. The reactor was then pressurized to the desired pressure (2.5 bars) with ethylene and the pressure was maintained for a predefined time (10 min). After releasing the residual ethylene pressure, air was injected through a gas injection tube and the suspension was maintained under constant oxygen pressure of 3 bars for 2 h with rigorous stirring (600 rpm) at 60° C. The calculated amount of CL monomer is added under inert atmosphere and the suspension was maintained at 60° C. for predefined time under rigorous stirring (600 rpm). The reaction is terminated by precipitation in acidic methanol (10% concentrated hydrochloric acid) to isolate and PCL materials. The block copolymer was extracted in THF in which PCL homopolymer is soluble. The block copolymers polyethylene-block-polycaprolactone was characterized by thermal analysis DSC, HT-SEC chromatography and ¹H NMR.

Analytical Techniques

¹H NMR analysis (¹H-NMR) carried out at 80-110° C. using deuterated tetrachloroethene (TCE-d₂) as the solvent and recorded in 5 mm tubes on a Varian Mercury spectrometer operating at frequencies of 400 MHz. Chemical shifts are reported in ppm versus tetramethylsilane and were determined by reference to the residual solvent.

Heteronuclear multiple-bond correlation spectra (HMBC) were recorded with pulse field gradients. The spectral windows for ¹H and ¹³C axes were 6075.3 and 21367.4 Hz, respectively. The data were collected in a 2560×210 matrix and processed in a 1K×1K matrix. The spectra were recorded with the acquisition time 0.211 s, relaxation delay 1.4 s and number of scans equal to 144×210 increments.

Solid-state ¹³C{¹H} Cross-Polarization/Magic-Angle Spinning (CP/MAS) NMR and ¹³C{¹H} Insensitive Nuclei Enhanced by Polarization Transfer (INEPT) experiments were carried out on a Bruker AVANCE-III 500 spectrometer employing a double-resonance H-X probe for rotors with 2.5 mm outside diameter. These experiments utilized a MAS frequency of 25.0 kHz, a 2.5 μs π/2 pulse for ¹H and ¹³C, a CP contact time of 2.0 ms and TPPM decoupling during acquisition. The CP conditions were pre-optimized using L-alanine. The ¹³C{¹H} INEPT spectra were recorded using the refocused-INEPT sequence with a J-evolution period of either ⅓ J_(CH) or ⅙ J_(CH) assuming a 1 J_(CH) of 150 Hz, i.e. for a J-evolution time of ⅓ J_(CH) the signals from CH and CH₃ groups are positive, while those of CH₂ are negative.

Size exclusion chromatography (SEC). The molecular weight in kg/mol and the Ð were determined by means of high temperature size exclusion chromatography which was performed at 160° C. using a high speed GPC (Freeslate, Sunnyvale, USA). Detection: IR4 (PolymerChar, Valencia, Spain). Column set: three Polymer Laboratories 13 μm PLgel Olexis, 300×7.5 mm. 1,2,4-Trichlorobenzene (TCB) was used as eluent at a flow rate of 1 mL·min⁻¹. TCB was freshly distilled prior to use. The molecular weights and the corresponding Ð were calculated from HT SEC analysis with respect to narrow polyethylene standards (PSS, Mainz, Germany). Size exclusion chromatography (SEC) of block copolymers was performed at 160° C. on a Polymer Laboratories PLXT-20 Rapid GPC Polymer Analysis System (refractive index detector and viscosity detector) with 3 PLgel Olexis (300×7.5 mm, Polymer Laboratories) columns in series. 1,2,4-Trichlorobenzene was used as eluent at a flow rate of 1 mL·min⁻¹. The molecular weights were calculated with respect to polyethylene standards (Polymer Laboratories). A Polymer Laboratories PL XT-220 robotic sample handling system was used as autosampler.

Differential scanning calorimetry (DSC). Melting (T_(m)) and crystallization (T_(c)) temperatures as well as enthalpies of the transitions were measured by DSC using a DSC Q100 from TA Instruments. The measurements were carried out at a heating and cooling rate of 10° C.·min⁻¹ from −60° C. to 160° C. The transitions were deduce d from the second heating and cooling curves.

Summarizing, for examples 1-5, step A) has been carried out using ethylene as the olefin monomer, 1 as the metal catalyst precursor, TIBA as the chain transfer agent, DEZ as a chain shuttling agent (expect for Example 4) and MAO (Examples 1-3) or borate (Examples 4-5) as the co-catalyst. During step B) oxygen has been used as the oxidizing agent. During step C) a ROP process has been carried out using CL as the cyclic monomer.

Comparative Example C1 has been carried out without oxidation step B). The rest was the same as for Example 1. Comparative Example C3 has been carried out without oxidation step B), the rest was the same as for Example 3. Comparative Example C4a has been carried out without polymerization step A) and Comparative example C4b has been carried out with steps B) and C). The rest was the same as for Example 4. Comparative Example C5 has been carried out without steps B) and C). The rest was the same as for Example 5.

For Example 6, step A) has been carried out using ethylene as the olefin monomer, 3 as the metal catalyst precursor and MAO as the co-catalyst. During step B) oxygen has been used as the oxidizing agent. During step C) a ROP process has been carried out using CL as the cyclic monomer. Comparative Example C6 has been carried out without step B). The rest was the same as for Example 6.

For Examples 7 and 8 step A) has been carried out using propylene as the olefin monomer, 1 as the metal catalyst precursor, MAO as the co-catalyst, TIBA as the chain transfer agent and DEZ as a chain shuttling agent. During step B) oxygen has been used as the oxidizing agent. During step C) a ROP process has been carried out using CL as the cyclic monomer. The difference between Examples 7 and 8 is the amount of chain shuttling agent.

For Example 9 step A) has been carried out using ethylene as the olefin monomer, 2 as the metal catalyst precursor, MAO as the co-catalyst, TIBA as the chain transfer agent and DEZ as a chain shuttling agent. During step B) oxygen has been used as the oxidizing agent. During step C) a ROP process has been carried out using CL as the cyclic monomer.

For Example 10 step A) has been carried out using ethylene as the olefin monomer, 3 as the catalyst precursor, MAO as the co-catalyst, TIBA as the chain transfer agent and DEZ as a chain shuttling agent. During step B) oxygen has been used as the oxidizing agent. During step C) a ROP process has been carried out using CL as the cyclic monomer.

Comparative Examples C-I and C-II have been carried out without a metal catalyst precursor and co-catalyst during step A) but with TIBA as the chain transfer agent, DEZ as a chain shuttling agent. Only steps B) and C) (for C-I) or step C) (for C-II) has been carried out. Table 2 shows the data obtained.

TABLE 2 Cat.^(a) Co- TIBA/ Yield^(g) Yield^(h) Ex. 1 2 3 catalyst^(b) DEZ^(c) C2 or C3^(d) O2^(e) CL¹ Crude final M_(n)(Ð)^(k)  1 14 — —   9 (M) 4/1 2.5 C2 (10) 5 (60) 35 (30) 9.8 5.3 5,400 (1.9) C1 14 — —   9 (M) 4/1 2.5 C2 (10) — 35 (30) 8.4 0.2 —  2 10 — —   9 (M) 4/1 2.5 C2 (10) 5 (60) 35 (30) 5.8 3.9 6,100 (2.4)  3 14 — —   9 (M) 4/1 2.5 C2 (5) 5 (30) 35 (30) 2.8 1.5 6,000 (2.5) C3 14 — —   9 (M) 4/1 2.5 C2 (5) — — 1.85 1.85 4,500 (2.8)  4 15 — —   20 (B) 2/— 2.5 C2 (10) 5 (30) 35 (30) 5.2 3.9 5,200 (3.1) C4a 15 — —   20 (B) 2/— — 5 (30) 35 (30) Trace s — — C4b 15 — —   20 (B) 2/— 2.5 C2 (10) — — 1.2 1.1 3,100 (2.8)  5 15 — —   20 (B) 2/ 2.5 C2 (10) 5 (30) 35 (30) 1.6 1.1 3,100 (2.5) 0.5 C5 15 — —   20 (B) 2/ 2.5 C2 (10) — — 1.2 — 2,400 (2.2) 0.5  6 — — 26 2.25 (M) —/— 2.5 C2 (10) 5 (30) 35 (30) 5.7 4.1 3,300 (2.6) C6 — — 26 2.25 (M) —/— 2.5 C2 (10) — 35 (30) 4.6 2.9 2,200 (2.5)  7 20 — —  4.5 (M) 2/ 2.5 C3 (15) 4 (60) 35 (60) 17.6 13.6 3,800 (2.2) 0.5  8 20 — —  4.5 (M) 2/ 2.5 C3 (15) 4 (60) 35 (60) 11.7 8.1 5,400 (1.9) 0.2  9 — 5 —   9 (M) 2/ 2.5 C2 (15) 4 (60) 35 (60) 6.7 4.1 7,500 (2.8) 0.5 10 — —  5   9 (M) 2/ 2.5 C2 (15) 4 (60) 35 (60) 4.8 2.9 6,100 (3.1) 0.5 C-I — — — — 4/1 — 5 (30) 35 (30) Trace n.d. n.d. C-II — — — — 4/1 — — 35 (30) Trace n.d. n.d. ^(a)metal catalyst precursors in μmol: 1: rac-Me₂Si(Ind)₂ZrCl₂; 2: rac-Me₂Si(Ind)₂HfCl₂; 3:[C₅Me₄CH₂CH₂NMe₂]TiCl₂; ^(b)co-catalyst in mmol, either MAO (M) or borate (B); ^(c)TIBA/DEZ: chain transfer agent (TIBA) in mmol/chain shuttling agent (DEZ) in mmol; ^(d)C2 is ethylene used as olefin during step A). The first value cited is the pressure in bar and the value between brackets is the time in minutes; ^(e)O2 is oxygen as the oxidizing reagent. The first value cited is the pressure in bar and the value between brackets is the time in minutes; fThe value cited is the amount in mmol. The value between brackets is the time in minutes; ^(g)Yield crude is the yield after precipitation in acidified methanol in grams. This may include mixtures of the desired block copolymer with one or more homopolymers; ^(h)Yield final is the yield after work up in THF. This is the yield of the block copolymer combined with the yield of homo-polyolefin which cannot be separated using this technique; ^(k)M_(n) is the number average molecular weight in gram/mol and the value between brackets is the polydispersity index.

From Table 2, the following can be observed.

When comparing Example 1 and comparative Example 1 (C1), it should be noted that for comparative Example 1 step B) has not been carried out. It can be seen that the crude yields for 1 and C1 are very similar.

When, however, the final products after work up (in this case extraction in THF) are compared, there is a large difference. For C1 there is hardly any product. This is due to the fact that no block-copolymer has been formed but merely a mixture of polyolefin homopolymer and PCL homopolymer.

Step B) of the present invention accordingly activates the chain end of the first polyolefin block in order to be able to form a second block attached to the first polyolefin block. From the comparative example 1 wherein step B) of oxidation is omitted it is clear that no block copolymer is obtained. The second polymer will polymerize separately during step C) e.g. under the influence of MAO but no block copolymer will be obtained.

When Example 1 and Example 2 are compared it is shown that lowering the amount of catalyst in step A) has reduced the yield.

Example 3 is similar to Example 1 but the duration of the ethylene polymerization in step A) has been halved and the duration of the oxidation in step B) has been halved. The effect is that the yield is reduced.

When Example 3 and Comparative Example 3 are compared, it is noted that for Comparative example 3 steps B) and C) are omitted. Hence only polyethylene homopolymer has been obtained. It can be clearly seen that the M_(n) is higher for Example 3 compared to C3, which shows the formation of the block copolymer.

Examples 4 and 5 use borate as a co-catalyst and TIBA as chain transfer agent without DEZ as chain shuttling agent. It is clear from the results that a block-copolymer can also be obtained in this manner.

When comparing Example 4 with comparative example C4a it is clear step A is omitted for C4a. Hardly any polymer has been obtained, not even a homopolymer of CL since there was no suitable catalyst for this homopolymerization present. In Comparative Example C4b only step A has been carried out. The polyethylene homopolymer has been formed. These examples show that extraction in THF is a very suitable way to separate the block copolymer from the homopolymer.

Example 5 is comparable to Example 4 but a chain shuttling agent is used. Comparative example C5 shows only step A) during which a homopolymer has been formed.

Examples 6 and 10 are carried out using a different catalyst. The catalyst precursor used is: C₅Me₄CH₂CH₂NMe₂TiCl₂.

Example 6 shows that a block copolymer according to the present invention can be obtained using this catalyst. Comparative Example C6 shows that without step B) there is the formation of product but this is mainly the homopolymer. Example 10 also shows the preparation of a block copolymer.

Examples 7 and 8 clearly show that a propylene-based block copolymer can be prepared by the present invention using propylene as olefin in step A).

A DSC thermogram trace of the product obtained in Example 7 after work up (extraction in THF) shows that in the product according to the present invention, the block copolymer PP-b-PCL has been formed as evidenced by two peaks.

Example 9 has been carried out using a hafnium catalyst which shows good results in the preparation of PE-b-PCL.

Comparative examples C-A and C-B show that no PCL has been formed when no catalyst is present.

These examples clearly show the effect of the present invention.

Thus, one or more aims of the present invention are obtained by the invention as further specified by the appended claims. 

The invention claimed is:
 1. A process for the preparation of a block copolymer comprising a first type of polyolefin block and at least one type of second polymer block, the process comprising the steps of: A) polymerizing at least one type of olefin monomer using a catalyst system to obtain a first polyolefin block containing a main group metal on at least one chain end; the catalyst system comprising: i) a metal catalyst or metal catalyst precursor comprising a metal from Group 3-10 of the IUPAC Periodic Table of elements; and ii) at least one type of chain transfer agent; and iii) optionally a co-catalyst; B) reacting the first polyolefin block containing a main group metal on at least one chain end obtained in step A) with at least one type of oxidizing agent to obtain a first polyolefin block containing at least one main group metal-functionalized oxidized chain end; and C) forming at least one second polymer block on the first polyolefin block, wherein as a catalytic initiator the main group metal-functionalized oxidized chain end of the first polyolefin block obtained in step B) is used, wherein during step C) no additional catalyst for the ROP, nucleophilic substitution or transesterification reaction is added.
 2. The process according to claim 1, wherein step C) of obtaining a block copolymer is carried out by ROP using at least one type of cyclic monomer.
 3. The process according to claim 1, wherein step C) of obtaining a block copolymer is carried out by at least one nucleophilic substitution reaction at a carbonyl group-containing functionality of at least one type of second polymer or wherein step C) of obtaining a block copolymer is carried out by transesterification of at least one type of second polymer comprising at least one carboxylic or carbonic acid ester functionality.
 4. The process according to claim 1, wherein step C) of obtaining a block copolymer is carried out by a combination of ROP using at least one type of cyclic monomer and at least one nucleophilic substitution reaction at a carbonyl group-containing functionality of at least one type of second polymer.
 5. The process according to claim 1, wherein the metal catalyst or metal catalyst precursor used in step A) comprises a metal from Group 3-10 of the IUPAC Periodic Table of elements and/or wherein the metal catalyst or metal catalyst precursor used in step A) comprises a metal selected from the group consisting of Ti, Zr, Hf, V, Cr, Fe, Co, Ni, Pd.
 6. The process according to claim 1, wherein the co-catalyst is selected from the group consisting of MAO, DMAO, MMAO, SMAO and fluorinated aryl borane or fluorinated aryl borate.
 7. The process according to claim 1, wherein the olefin monomer used in step A) is selected from the group consisting of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-cyclopentene, cyclohexene, norbornene, ethylidene-norbornene, and vinylidene-norbornene and one or more combinations thereof.
 8. The process according to claim 2, wherein the cyclic monomer used during ROP in step C) is a polar monomer, selected from the group consisting of lactone, a lactide, a cyclic oligoester (e.g. a di-ester, a tri-ester, a tetra-ester, a penta-ester or higher oligoesters), an epoxide, an aziridine, a combination of epoxide and/or aziridine and CO₂, a cyclic anhydride, a combination of epoxide and/or aziridine and a cyclic anhydride, a combination of epoxide and/or aziridine and CO₂ and a cyclic anhydride, a cyclic N-carboxyanhydride, a cyclic carbonate, a lactam and one or more combinations thereof.
 9. The process according to claim 2, wherein the cyclic monomer used during ROP in step C) is a cyclic monomer comprising a carbonyl group-containing functionality and at least 10 consecutive carbon atoms in the ring/cycle.
 10. The process according to claim 3, wherein the second polymer block comprising at least one carboxylic or carbonic acid ester functionality or carbonyl-group containing functionality is selected from the group consisting of a polyester, a polycarbonate, a polyamide, a polyurethane, a polyurea, a random or block poly(carbonate-ester), poly(carbonate-ether), poly(ester-ether), poly(carbonate-ether-ester), poly(ester-amide), poly(ester-ether-amide), poly(carbonate-amide), poly(carbonate-ether-amide), poly(ester-urethane), poly(ester-ether-urethane), poly(carbonate-urethane), poly(carbonate-ether-urethane), poly(ester-urea), poly(ester-ether-urea), poly(carbonate-urea), poly(carbonate-ether-urea), poly(ether-amide), poly(amide-urethane), poly(amide-urea), poly(urethane-urea) or one or more combination thereof.
 11. The process according to claim 1, wherein the chain transfer agent is a main group metal hydrocarbyl or a main group metal hydride.
 12. The process according to claim 11, wherein the chain transfer agent is selected from the group consisting of trialkyl boron, dialkyl boron halide, dialkyl boron hydride, diaryl boron hydride, dialkyl boron alkoxide, dialkyl boron aryloxide, dialkyl boron amide, dialkyl boron thiolate, dialkyl boron carboxylate, dialkyl boron phosphide, dialkyl boron mercaptanate, dialkyl boron siloxide, dialkyl boron stannate, alkyl boron dialkoxide, alkyl boron diaryloxide, alkyl boron dicarboxylate, alkyl boron diphosphide, alkyl boron dimercaptanate, alkyl boron disiloxide, alkyl boron distannate, boron hydride dialkoxide, boron hydride diaryloxide, boron hydride diamide, boron hydride dicarboxylate, boron hydride diphosphide, boron hydride dimercaptanate, boron hydride disiloxide, boron hydride distannate, trialkyl aluminum, dialkyl aluminum halide, dialkyl aluminum hydride, dialkyl aluminum alkoxide, dialkyl aluminum aryloxide, dialkyl aluminum amide, dialkyl aluminum thiolate, dialkyl aluminum carboxylate, dialkyl aluminum phosphide, dialkyl aluminum mercaptanate, dialkyl aluminum siloxide, dialkyl aluminum stannate, alkyl aluminum dialkoxide, alkyl aluminum diaryloxide, alkyl aluminum dicarboxylate, alkyl aluminum diphosphide, alkyl aluminum dimercaptanate, alkyl aluminum disiloxide, alkyl aluminum distannate, aluminum hydride dialkoxide, aluminum hydride diaryloxide, aluminum hydride diamide, aluminum hydride dicarboxylate, aluminum hydride diphosphide, aluminum hydride dimercaptanate, aluminum hydride disiloxide, aluminum hydride distannate, trialkyl gallium, dialkyl gallium halide, dialkyl gallium hydride, dialkyl gallium alkoxide, dialkyl gallium aryloxide, dialkyl gallium amide, dialkyl gallium thiolate, dialkyl gallium carboxylate, dialkyl gallium phosphide, dialkyl gallium mercaptanate, dialkyl gallium siloxide, dialkyl gallium stannate, dialkyl magnesium, diaryl magnesium, alkyl magnesium halide, alkyl magnesium hydride, alkyl magnesium alkoxide, alkyl magnesium aryloxide, alkyl magnesium amide, alkyl magnesium thiolate, alkyl magnesium carboxylate, alkyl magnesium phosphide, alkyl magnesium mercaptanate, alkyl magnesium siloxide, alkyl magnesium stannate, dialkyl calcium, alkyl calcium halide, alkyl calcium hydride, alkyl calcium alkoxide, alkyl calcium aryloxide, alkyl calcium amide, alkyl calcium thiolate, alkyl calcium carboxylate, alkyl calcium phosphide, alkyl calcium mercaptanate, alkyl calcium siloxide, alkyl calcium stannate, dialkyl zinc, alkyl zinc halide, alkyl zinc hydride, alkyl zinc alkoxide, alkyl zinc aryloxide, alkyl zinc amide, alkyl zinc thiolate, alkyl zinc carboxylate, alkyl zinc phosphide, alkyl zinc mercaptanate, alkyl zinc siloxide, alkyl zinc stannate, and or more combinations thereof.
 13. The process according to claim 1, wherein the oxidizing agent in step B) is selected from the group consisting of O₂, CO, O₃, CO₂, CS₂, COS, R²NCO, R²NCS, R²NCNR³, CH₂═C(R²)C(═O)OR³, CH₂=C(R²)(C═O)N(R³)R⁴, CH₂=C(R²)P(═O)(OR³)OR⁴, N₂O, R²CN, R²NC, epoxide, aziridine, cyclic anhydride, R³R⁴C═NR², R²C(═O)R³, and SO₃, where R², R³, and R⁴ are each independently selected from hydrogen or SiR⁷ ₃, SnR⁷ ₃ or a C1-C16 hydrocarbyl; and where each R⁷ is independently selected from hydride, halide or C1-C16 hydrocarbyl.
 14. The process according to claim 11, wherein the chain transfer agent is selected from the group consisting of: hydrocarbyl aluminum, hydrocarbyl magnesium, hydrocarbyl zinc, hydrocarbyl gallium, hydrocarbyl boron, hydrocarbyl calcium, aluminum hydride, magnesium hydride, zinc hydride, gallium hydride, boron hydride, calcium hydride and one or more combinations thereof.
 15. The process according to claim 12, wherein the chain transfer agent is selected from the group consisting of trimethyl aluminum (TMA), triethyl aluminum (TEA), tri-isobutyl aluminum, tri(t-butyl) aluminum di(isobutyl) aluminum hydride, di(n-butyl) magnesium, n-butyl(ethyl)magnesium, benzyl calcium 2,6-di(t-butyl)-4-methyl-phenoxide, dimethyl zinc, diethyl zinc, trimethyl gallium, or triethylboron, 9-borabicyclo(3.3.1)nonane, catecholborane, and diborane and one or more combination thereof.
 16. The process according to claim 13, wherein the oxidizing agent in step B) is selected from the group consisting of O₂, O₃, N₂O, epoxide, aziridine, CH₂=C(R²)C(═O)OR³, CH₂=C(R²)(C═O)N(R³)R⁴, CH₂=C(R²)P(═O)(OR³)OR⁴, R²C(═O)R³, R³R⁴C═NR², where R², R³, and R⁴ are each independently selected from hydrogen or SiR⁷ ₃, SnR⁷ ₃ or a C1-C16 hydrocarbyl; and where each R⁷ is independently selected from hydride, halide or C1-C16 hydrocarbyl.
 17. The process according to claim 1, wherein step C) is carried out directly after step B).
 18. The process according to claim 1, wherein the main group metal of the first polyolefin block containing the main group metal on at least one chain end is derived from the at least one chain transfer agent. 